129356345-29904848-Scaffolding-Standard.pdf

INDIAN OIL SAFETY MANAGEMENT SYSTEM [ SURAKSHA ]

SCAFFOLD SAFETY

ISMS STANDARD - 1007 First Edition, November 2007

INDIAN OIL CORPORATION LIMITED REFINERIES HEAD OFFICE

SCOPE COMPLEX, CORE – 2, 7, INSTITUTIONAL AREA, LODHI ROAD,

NEW DELHI – 110 003

1SIGN. & STAMP OF TENDERER 1 of 104

ISMS STANDARD - 1007 First Edition, September 2007

SCAFFOLD SAFETY

IMPORTANT

Mandatory requirements (or "must") are characterised by the word "SHALL" throughout the text. Advisory requirements orrecommendations are indicated by the word "SHOULD."

Prepared by :

COMMITTEE ON STANDARDISATION OF SAFETY SYSTEMS

INDIAN OIL CORPORATION LIMITED REFINERIES HEAD OFFICE

SCOPE COMPLEX, CORE – 2, 7, INSTITUTIONAL AREA, LODHI ROAD,

NEW DELHI – 110 003


NOTES

This document is prepared for use in the Indian Oil Corporation Limited, Refineries Division. This is the property of Indian Oil Corporation Limited, Refineries Division and shall not be reproduced or copied and loaned or exhibited to otherswithout written consent from Executive Director (Operation), IOCL, Refineries Division, New Delhi.

Though every effort has been made to assure the accuracy and reliability of data contained in this document, Committee hereby disclaims any liability or responsibility for loss /damage resulting from its use.

This document is intended only to supplement and not replace the prevailing statutory requirements.


PREFACE

Over the years of operation, Refineries under the umbrella ofIndian Oil Corporation Limited [i.e. IOCL], adopted variety of safety practices in line with the requirements of statutes, national and international norms & Standards and safety management system in safety practices. Based on safety assessment studies and some serious accidents that occurred in the recent past in IOCL Refineries, emphasized the need for the review of existing safety practices of IOCL Refineries.

With this in view, it has been decided at IOCL (RD), Head Office (H.O.) to standardize the key Safety Management System elements for the Refineries Division exploiting internal knowledge bank and resources. In accordance with this decision, a committee has been constituted by Executive Director (Operation), IOCL, H.O., for the said purpose under his convenership.

The present document on “Scaffold Safety”, prepared by the Committee on Standardisation of Safety Systems, is based on the various national and international codes, best practicesprevailing in the IOCL Refineries and accumulated knowledge & experience of the members. Provisions of this standard if implemented objectively will help in improving safety at work places and thereby reducing the possibility of undesired incidents in IOCL, Refineries.

No change in the standard is permitted at unit level. Suggestionsfor amendments / changes, if any, to this standard shall be addressed to:

The Executive Director (Operation), Indian Oil Corporation Limited

Refineries Head OfficeScope Complex, Core – 2,

7, Institutional Area, Lodhi Road, New Delhi – 110 003


COMMITTEE ON SCAFFOLD SAFETY

LIST OF MEMBERS

Sl. No. Name Designation Location Position in

Committee

1. Shri N. K. Bansal ED (O) R&P, H.O. Convener

2. Shri S. K. Das CM (QA & Systems) Mathura Refinery Member

3. Shri A. Chaudhuri CPNM Haldia Refinery Member

4. Shri D. Chakraborty CTSM Barauni Refinery Member

5. Shri Sunil Kumar CM (F&S) Gujarat Refinery Member

The committee expresses sincere gratitude to Shri A. Panda, GM (S&EP), H.O., New Delhi for his immense support and guidance in formulating this standard. The committee also extends sincere thanks to Shri G. B. Tolmare, CM (SHE), C.O., New Delhi for his contribution, involvement and sharing of knowledge & experience which has helped in framing the standard.

SIGN. & STAMP OF TENDERER 5 of 104 5

CONTENTS

SECTION ATTRIBUTE PAGE NO.

1. PURPOSE 6 2. SCOPE 63. DEFINITIONS & ABBREVIATIONS 6 4. INTRODUCTION 9 5. HAZARDS OF SCAFFOLD 9 6. GENERAL REQUIREMENTS 10 7. SAFETY FEATURES COMMON TO ALL SCAFFOLDS 11 8. TYPE OF SCAFFOLDS 21 8.1 INDEPENDENT TIED SCAFFOLD 22

8.1.1 LIGHT DUTY INDEPENDENT TIED SCAFFOLD 228.1.2 MEDIUM DUTY INDEPENDENT TIED SCAFFOLD 23 8.1.3 HEAVY DUTY INDEPENDENT TIED SCAFFOLD 24 8.2 MOBILE TOWER SCAFFOLD 25

8.3 BIRDCAGE SCAFFOLD 27 8.4 TRUSS SCAFFOLD 28 8.5 INDEPENDENT SCAFFOLD 30 8.6 TRESTLE SCAFFOLD 30 8.7 SYSTEM SCAFFOLDING 32 8.8 SLUNG SCAFFOLD 32

8.9 DROP SCAFFOLD 33 8.10 BRACKET SCAFFOLD 34

9. PORTABLE / MOBILE LADDER 36 10. TEMPORARY SRAIRWAYS 39 11. TRAINING 40 12. AUDIT FOR SCAFFOLD AND WORK AT HEIGHT 41 13. REFERENCE 42

ANNEXURES

I. PRE ERECTION CHECKLIST FOR SCAFFOLD 43 II. CHECK-LIST FOR SCAFFOLD 45 III. CERTIFYING TAGS FOR SCAFFOLD 46 IV. SCAFFOLD PIPES, BOARDS AND FITTINGS 47 V. SAFE ERECTION OF SCAFFOLDS 53 VI. INSPECTION OF LADDER, PIPES & BOARDS 84 VII. TYPES OF SCAFFOLDS 92 VIII. PERSONAL PROTECTIVE EQUIPMENT 110 IX. FORMAT FOR WORK AT HEIGHT PERMIT 112

& MEDICAL CERTIFICATE


SCAFFOLD SAFETY

1. PURPOSE

The purpose of this standard is to describe procedures and guidelines to ensure safety in various types of steel tubular scaffolds, erected formaintenance and construction activities, including procedure for safe erection and dismantling with access ladders, which is an integral part of scaffold.

2. SCOPE

This standard shall be applicable to all the Refinery premises of Indian Oil Corporation Limited, wherever any tubular scaffold shall be erected, used and dismantled, by our employees and contractor employees.

3. DEFINITIONS AND ABBRIVIATIONS

3.1 TUBULAR MEMBERS (Refer Figure 5.1)

STANDARD: A tube used as a column or vertical in the construction of a scaffold, and transmitting a load to the ground via a base plate. It is alsoknown as an Upright or Column.

PUNCHEON - A vertical tube supported otherwise than upon the ground or a base plate.

LEDGER - A tube spanning horizontally and tying a scaffold longitudinally. It may also act as a support for put logs, transoms or board bearers.

TRANSOM - A tube spanning across ledgers to tie a scaffold transversely,which may also support a working platform.

BOARD BEARER - A tube spanning across ledgers between transoms to support a working platform.

PUTLOG - A tube or other member spanning horizontally between a ledger and the wall of a building. It may have a special formed end, which may be detachable for the purpose of fitting into brickwork.

RAKER (Also known as a Strut or Spur) - An inclined load bearing tube having a bearing on the ground or on an adjacent structure. Refer Figure 5.9

BRACE - A tube incorporated diagonally across two or more members in a scaffold and fixed to them to afford stability.

TIE - A tube used to connect a scaffold to a rigid anchorage. Refer Figure 5.5 to Figure 5.8).


GUARDRAIL - (Also wrongly known as a Handrail) - A tube connected at the edge of platform and other places to prevent persons falling from platform ofplace.

MIDRAIL-A horizontal rail approximately midway between the top rail of a guardrail system and the platform.

HANDRAIL - Tube used on stairs before permanent handrails, banisters, etc.fitted to prevent the fall of persons. Refer Figure 5.1 and 5.2 for tubular members of scaffold.

3.2 SCAFFOLD FITTINGS

BASE PLATE - A 6"X6" (150 mm x 150 mm) - steel plate providing a flat bearing surface for load distribution from standards. It has an integral spigot and fixing holes for use with sole plates. Refer Figure 4.3.

ADJUSTABLE BASE PLATE - Used for compensating variations in ground levels. Also used for strutting and shoring. Refer Figure 4.4.

DOUBLE COUPLER- A load-bearing coupler used for connecting two tubestogether at right angles. It is also known as a Right Angle or Ninety-DegreeCoupler or Clip. Refer Figure 4.9.

UNIVERSAL COUPLER - Load-bearing coupler used for connecting two tubestogether at right angles or in parallel. It is also known as S.G.B. or Band and Plate Coupler. Refer Figure 4.2.

PUTLOG COUPLER - A non-load-bearing coupler used for fixing two tubes atright angles, e.g., intermediate put logs or board bearers to ledgers. It is also known as a Putlog Clip. Refer Figure 4.8

PUTLOG OR BRACE COUPLER (SGB type) - This coupler whilst primarilydesigned for securing putlogs and transoms to ledgers, also conforms to the requirements for a bracing coupler. Refer Figure.-4.2.

SWIVEL COUPLER - Used for connecting two tubes together at any angle through 360 degrees. It is a load bearing coupler. Refer Figure.-4.6.

END TO END COUPLER - Used for connecting two tubes end to end. It is also known as a Sleeve Coupler. Refer Figure 4.7.

JOINT PIN - Used for connecting two tubes end to end. Fitted internally itexpands to apply grip against the wall of the tube. It is also known as a Spigot. Refer Figure 4.10.

PUTLOG END- Used for converting an ordinary tube into a putlog.

TOE BOARD CLIP - Used for fixing toe board to standard. Refer Figure.4.2

REVEAL PIN A fitting used for tightening a reveal tube between two opposing


surfaces. Refer Figure 4.13.

REVEAL TUBE - A tube fixed by means of a threaded fitting (reveal pin)between two opposing surfaces of a building or structure to form a solid anchorage to which a scaffold may be tied. Refer Figure 5.7.

SPIGOT - A pinned or bolted internal fitting to join one standard to another coaxially. Used in system scaffolds. Refer Figure 4.11.

SPIGOT PIN - A pin or bolt placed transversely through the spigot and thescaffold standard to prevent the spigot from pulling out of the tube. Also knownas tension pin, dowel pin, and coupling pin. Refer Figure 4.11.

3.3 GENERAL TERMS

SOLE PLATE - A timber or steel member of adequate size and suitable qualityused to distribute the load from the base plate over an area of ground. It is alsoknown as Spreader. Refer Figure 4.14.

BAY - The space between two adjacent standards along the face of a scaffold. Refer Fig.5.4.

LIFT - The height from the ground or floor to the lowest ledger, or the vertical distance between two adjacent ledgers. Refer Figure 5.3.

TOE BOARD - A board positioned at the edge of a platform or place so as to prevent persons, tools and materials falling from the platform or place. It is alsoknown as a Kicking Board. Refer Figure 5.1.

DECKING - A close-boarded scaffold platform. Refer Figure 5.24.

WORK STAGE - Purpose made decking for use on towers, trestles, rooftrusses, etc. It can be used over greater spans than ordinary scaffold boards. Itis also known as staging.

UNIT BEAM - A Purpose-made lattice beam incorporated into a scaffold structure to form a bridge where openings are necessary.

TWO-WAY TIE - A tie which prevents movement of the scaffolding both to and from the building or structure to which it is secured. Refer Figure 5.5.

COLUMN BOX-TIE - Two-way tie secured to a vertical column with tubesforming a 'box' round the column. Refer Figure 5.6.

PARALLEL COUPLER - Short tube secured longitudinally across an end toend joint in tubing to strengthen the joint. Refer Figure 5.27.

JUNCTION - The intersection of a series of tubes.

BUTTRESS - A well-braced tubular structure erected against an existing scaffolding structure to strengthen it.


LONGITUDINAL BRACING (Also known as Face or Facade Bracing) - Tubessecured diagonally across the face of a scaffold to ensure stability. Refer Figure 5.1.

LEDGER BRACING - Tubes secured diagonally between lifts from ledger to ledger or standard to standard to ensure stability. It is also known as Cross orWind Bracing or Transverse. Refer Figure 5.1.

FAN - A Scaffold platform cantilevered from the main structure at point below the working level and designed to catch any materials etc. that might fall.

SCAFFOLD LASHING - Wire rope of 1/2" (6.4 mm) diameter used for lashing ladders, etc. Not to be used for suspending or anchoring scaffolds, or for lifting operations. Refer Figure 6.3.

LADDER- A device used for climbing vertically between levels, including:

a. EXTENDED LADDER - A portable ladder that cannot support itself but can be adjusted in length. It consists of two sections that are arranged to permitlength adjustment.

b. STRAIGHT LADDER - A portable ladder that consists of one section thatdetermines its overall length. It cannot support itself or be adjusted in length. Refer Figure.6.1.

SAFETY HARNESS – Personal Protective Equipment consists of waist belttogether with shoulder straps and leg straps. Refer Figure. 8.1.

LANYARD- The line used to connect the safety harness to anchorage point. Refer Figure.8.3.

4. INTRODUCTION

Tubular scaffolds are used in refineries as temporary work places at height (supported of underhung) for carrying out job safely by persons and to support for plant & materials used in buildings, construction, maintenance, repair and demolition work, etc.

All scaffolds shall be erected, free from any fall hazard with guardrail system and measures shall be in place to reduce the consequence of fall, should theyoccur. Safe scaffold is a basic requirement of the job, carried out at height. Safety during erection and dismantling of scaffold is equally important and mustbe adhered to ensure no accident while working.

5. HAZARDS OF SCAFFOLD

Occurrence of accidents caused by fall of working person from a height or due to collapse of scaffold show clearly the importance of properly constructed and maintained ladders and scaffolds. Apart from collapse the principal hazardsare:

• Slipping of unsecured ladders


• Use of unsuitable, sub standard or faulty materials • Inadequately supported scaffold boards • Inadequate or irregular platform widths or substandard platform • Omission of guardrails or toe boards • Failure to secure scaffold to the permanent structure or to brace it adequately. • Overloading the platforms and scaffold, etc.

6. GENERAL REQUIREMENTS

6.1 TUBE (Refer Fig.4.1)

All steel tubing to be used for scaffolding shall be of 1 ½ inch nominal bore size heavy duty, and grade YST 22 as specified in IS: 1161, confirming to IS: 2750 or BS 1139. Refer Figure 4.1.

Tube shall be free of cracks, surface flaws and other defects.

Tube shall not deviate from straight line by more than 1/600 of its length measured at centre of its length. Straightening of tubes shall only be carried outon a straightening machine. Deformed section of tube shall be cut out. Refer Figure 6.4.

All tubes shall be maintained in a clean condition and regularly inspected. Step shall be taken to combat corrosion by means of varnishing / painting of external surface of tubes. Where the section of tube is deformed through bending, thisshall be cut out.

6.2 FITTINGS (Refer Figure 4.2)

Specification of scaffold fittings such as couplers, clips, etc., shall conform to IS: 2750 (material of construction shall confirm to steels of schedule II ofIS:1570) / BS 1139 / EN 74.

Fittings should be regularly examined for any developed defects. Moving parts shall be regularly lubricated for ease movement. In case of any defect scaffold,the fittings shall be rejected/ scrapped.

Safe working loads of coupling shall be considered as part of the following table while selecting for use in a scaffold:

Safe Working Loads for Individual Couplers TYPE OF COUPLER TYPE OF LOAD MINIMUM SAEF WORKING

LOAD (SWL)* Right-angle coupler (double coupler/ load bearing coupler)

Slip along a tube SWL= 6.25 kN (1,400 lb)

Swivel Coupler (Adjustable coupler)

Slip along a tube SWL= 5.3 kN (1,190 lb)

End-to-End Coupler (Sleeve coupler)

Tension Bending

SWL= 3 kN (675 lb) SWL= 0.59 kN-m (435 lb/ft.)


Singer coupler (Putlog/ Bearer coupler)

Force to pull the tube axially out of the coupler

SWL= 0.53 kN (120 lb.)

Joint pin Tension SWL = 0 kN (0 lb) Girder Coupler (drop forged

Shear SWL = 30 kN per pair (6,740 lb.)

* - Reproduced from BS: 3973, Table-17.

6.3 BOARDS (Refer Figure 4.14)

Timber scaffold boards shall conform to IS: 3629 or BS 2482. The fabricated boards of similar specification, made of laminated timber or steel can also be used. As wood is combustible material, steel boards shall be used in refineries,particularly in operating areas.

Looking at the face of the board, the end shall not be split up more than 12"(300 mm) fixed with the iron hoop.

Looking at the edge of the board, not more than half of the depth shall be knot wood.

Looking along the board from one end it must not be twisted by more than ½" (12 mm) thick.

Boards, which are split, decayed or warped, shall not be used, but the parts affected may be cut off to obtain shorter boards. (Refer Fig. 6.5 & 6.6)

Wooden boards shall not be painted or treated in any way that may conceal defects

Boards used for scaffold decking upto 2”thickness shall be not less 8" (200mm) wide, and for boards more than 2" (50 mm) thick, not less than 6" (150mm)wide.

Timber boards shall not be used where they are in contact with hot lines orsurfaces or in operating areas of refineries, which could cause fire. Metallic boards shall be used in these cases.

7. SAFETY FEATURES COMMON TO ALL SCAFFOLDS

• All scaffold materials, site of erection and preparation for erection shall bechecked by site engineer / engineer in-charge and area in-charge using formatfor “Pre-Erection Check-list for Scaffold”, enclosed as Annexure-I. All the conditions of checklist shall be complied jointly by site engineer / engineer in-charge and area in-charge, before proceeding for erection. All erection/dismantling shall be governed by standard on “Work Permit System”. For erection/ dismantling upto 2 M height “Cold Work Permit” shall also be required. For jobs at a height beyond 2M “Working at Height Permit” is required. “Medical Fitness Certificate” is also required in prescribed format (Refer Annexure-IX) for working at height (including erection/ dismantling of scaffold beyond 2M


height). For details, please refer standard on “Work Permit System”. The medical certificate shall be issued by Registered Medical Practitioner and shall be valid for a period not exceeding 1 year.

• The top of scaffold must clear the overhead electric cable by following gaps:

INSULATED LINES Voltage Minimum Distance Alternatives

Less than 300 Volts

1 meter 2 times the length of the line insulator, but never less than

3 meters 300 Volts to 50 3 meters kV

3 meters plus 100 mmh 1 kV over 50 kV UNINSULATED

Voltage Minim Alternatives 2 times the length of the line Less than 50 kV 3 meter

3 meters plus 100 mm

• Every scaffold and scaffold component (including platform units) shall be capable of supporting, without failure, its own weight (dead load) and at leastfour (4) times the maximum intended load (live load) applied or transmitted to it(D+4*L). Se

• All scaffolds shall have a specified load rating, corresponding to the maximumintended load, of either Light-duty, Medium-duty, or Hea v y -duty. Fordesign, the

• Under any circumstances scaf

7

A good base is essential. The ground or floor on which the scaffolding is going to stand shou

Sole plates at least 9" x 1½" (230 mm x 40 mm) cross section are required to spread the load on earth, made up ground, asphalted surface etc. Refer Figure 5.12. Sole plates shall extend under at least two standards and joints shall be positioned so that they fall within one half to one third of the distance between any two adjacent

Small timber pads may be used on solid bearing, such as concrete, where there is no risk of the standard and base plate sinking or becoming displaced.

SIGN. & STAMP OF TENDERER 13 of 104

More than 50 kV for eac

LINES um Distance

More than 50 kV for each 1 kV over 50 kV

insulator, but never less than 3 meters

lf-weight of platform units (including planks) shall be considered asdead load.

maximum intended load (live load) shall be taken as the scaffold’s load rating.

folds and scaffold components shall not be loadedin excess of their load rating.

.1 FOUNDATION

ld be carefully examined. Soil or made up ground shall be consolidated.

standards. At the end standard the sole plate shall project a similar distance.

Any other make shift arrangement e.g. barrels, boxes, loose bricks or concrete

13

blocks shall not be used as a substitute for sole plate for construction of a scaffold. Refer Figure 5.12 and 5.13.

7.2 STANDARDS

Standards shall be pitched on base plates and sole plates or timber pads. Refer Figure 5.12 and 5.13.

Joints in standards should not occur in the same lift. Joints should be arranged so that they occur as near as possible to a ledger. All standards shall be vertical. Refer Figure 5.23. End-to-end coupler should join two standards.Refer Fig. 5.14 A. The parallel couplers shall be used for reinforcement.Standard shall be vertical and plumbed as shown in Figure 5.14 A and 5.14 B.

7.3 LEDGERS / TRANSOMS

Ledgers shall be securely fixed to standards with double or universal load-bearing couplers and shall be horizontal. Joints in ledgers should be staggered,i.e. joints in adjacent ledgers shall not occur in the same bay. Refer Figure 5.23. It is desirable that these joints be made with sleeve couplers. If joint pinsare used these shall be placed at about one-quarter to one-third the span between the standards, not at mid-span.

Ledgers / Transoms shall be horizontal and it’s horizontality shall be measured and ensured using Spirit level as shown in Figure. 5.14 B.

7.4 BRACING

Bracings are reinforcing members, gives strength and stability to scaffold. All scaffolds shall be provided with bracings, i.e., longitudinal bracing and ledger/ transverse bracing. Refer Figure.5.1.

7.5 TIES / RAKERS

Ties and rakers are provided in scaffolds to give support and stability. Though these are not recommended for all types of scaffolds, however it shall be used wherever recommended for different types of scaffold to give stability. Differenttypes of tie arrangement have been shown in Figure.5.5 to 5.7 including use ofreveal pin.

All scaffolds of height more than 3 times of their minimum base dimension are required to be tied. For close view of reveal pin refer Figure. 4.13.

Rakers are used to gives additional support to scaffold. This can be used in many types of scaffold. Refer Figure.5.9

7.6 DECKING

All decking shall be close-boarded, each board resting evenly on at least three supports. Boards shall oversail end supports by at least 2" (50 mm) but shall not oversail by more than four times their thickness.


Supports for scaffold boards (transoms, putlogs, etc.) shall be spaced with due regard to the nature of the platform and the load it will bear. Refer Figure. 5.15& 5.16.

Maximum permissible distances between supports for scaffold boards (transoms, putlogs, etc.), are as given below:-

THICKNESS VIS-A-VIS MAXIMUM DISTANCE

SCAFFOLD BOARD BETWEEN SUPPORTS

1¼" (32 mm) 3' 3" (990 mm)

1½" (40 mm) 5' 0" (1.520 m)

2" (51 mm) 8' 6" (2.590 m)

Note: These distances are the maximum allowed for single planking, but these must be reduced whenever the anticipated load or the nature of the platformmakes a smaller distance necessary for safety. Wherever fabricated steel platform is used instead of timber of equivalent strength the above guidelinesshould be followed. In such cases guidelines of manufacturer should be referred.

Except on decking contiguous to the curved surface of a cylindrical or spherical structure, boards shall be laid flush wherever possible. Where overlaps are unavoidable, suitable beveled pieces shall be provided to reduce the risk oftripping.

Boards shall be laid with no openings more than 1 inch (25 mm) between adjacent boards or scaffold member.

Decking shall be kept free from unnecessary obstructions and from materials, rubbish and projecting nails.

Decking which has become slippery with oil, or other substance shall be immediately sanded, cleaned or otherwise treated. Refer Figure 5.24.

The slope of a gangway or run, shall not exceed 1” vertical to 1½" horizontal.Slopes of more than 1 vertical to 4 horizontal shall have stepping laths at suitable intervals. Laths are to extend the full width of the gangway or run, except that gaps of 4" (100 mm) may be left at the centre to facilitate the movement of barrows.

Boards shall be secured from movement. Refer Figure 5.17.

7.7 GUARDRAILS AND TOEBOARDS

Guardrails and toe boards shall be fitted at edges of decking from which persons or material could fall a distance of more than 6' 6" (1980 mm). Guardrails shall not be less than 3' (920 mm) and not more than 3' 9" (1150


mm) high, and the space between toe board and guardrails shall not exceed 2' 6" (760 mm). Mid-rail should be used additionally in between toe board and guardrail. Refer Figure.5.1.

Guardrails and toe boards shall be fitted to the inside of standards to preventoutward movement, unless they are so designed and used as to prevent such movement.

Toe boards should be 8" (200 mm) high and secured in position by toe board clips or other means.

Guardrails and toe boards may be removed or partially erected for the time being and to the extent necessary for the access of men or the movement ofmaterials. These shall be replaced or erected as soon as practicable.

7.8 MATERIAL GUARDS

Where materials are to be stacked on a working platform or working placeabove the height of the toe boards, suitable barriers shall be positioned so as to prevent the fall of such material from the platform or place. The inadequateheight of material guard may lead to unsafe falling of material. Refer Figure.6.8.

7.9 ACCESS

Access to a working platform is best achieved by providing a separate ladder tower or cantilevered access platform so as not to obstruct the platform and to minimize the possibility of persons falling through the gap in the guardrail ordecking. Refer Figure 5.25 & 5.26.

7.10 GIN WHEELS

Gin wheels are widely used for lifting light loads up to 112 lb (50.8 kg) on to scaffolding. There are two types of wheel in general use, the ring-type and the hook-type. The ring-type shall preferably be used. Refer Figure 4.12.

The supporting tube shall be attached to two standards in the case of anindependent tied scaffold. Double or universal load-bearing couplers shall be used to attach the supporting tube to the standards. The point of suspension of the gin wheel shall not project more than 2' 6" (760 mm) beyond the outer supporting tube. If the distance between the point of suspension and the outer supporting standard is more than 1' (300 mm) a diagonal brace should be fitted.

A coupler shall be fitted to the supporting tube on either side of the ring to prevent movement.

Ropes used with gin wheel shall be of suitable size and conform to BS 2052. Each rope shall be marked for identification.

7.11 INCOMPLETE SCAFFOLDING


Where scaffolding is incomplete, whether it is during erection, dismantling or alteration, access to those parts, which are incomplete, shall be barred and warning notices displayed in form of “RED TAG”. Please refer Annexure-III

7.12 WORKMANSHIP

Scaffolding shall be erected, altered and dismantled by experienced workmen working under the direction of a trained and experienced supervisor.

Standard shall be set accurately, in plan and vertically, by using a spirit level or plumb line at each lift. Ledgers shall be set horizontally with a spirit level, or by using horizontal lines on the building or structure.

Scaffolding couplers shall be tightened only with the tools recommended by the manufacturers of the couplers. The use of a spanner or tool that gives a leverage greater than that of the tool recommended, is liable to cause damage to bolt studs with the result that not only the grip of the coupler on the tube will be impaired, but also the coupler will be rendered unserviceable.

Scaffolding materials and other objects shall not be dropped, thrown tipped orshot from heights.

The area below working platform, where risk of material falling form top is a probability shall be barricaded with warning tape and boards to forbid entry ofpersons.

7.13 INSPECTIONS

All scaffolding including access ladder shall be inspected after completion oferection, alternation, repair, at least after every seven days from the day ofcompletion and if weather likely to have affected stability. Main points to be checked during inspections are as follows:

• Pitching of standard base on base plates and adequacy of timber/steel sole plates

• Alignment and condition of standard including damage and displacement or undue deflection of ledger

• Ties & Braces-Adequate and effective • Selection, type and tightness of couplers • Boards Sound, close-laid, properly supported, and secured from movement • Guardrails and Toe boards/ material guard (if required) in place • Ladders In good condition properly supported and secured. For detail refer

section-10.

Inspection of scaffold shall be done before erectionin prescribed format, “Pre-erection checklist for scaffolds” (Attached as Annexure-I). All the requirements of checklist must be complied. All scaffolds shall be inspected and certified inprescribed form (enclosed as Annexure-II) by scaffold supervisor and trained site engineer. All scaffold shall be tested and certified at frequency notexceeding 7 days or whenever some modification, alteration, repair is carried


out or whenever the scaffold is exposed to adverse weather condition such ashigh wind, heavy rain etc.

SCAFFOLD TAG: Tags for display on scaffold shall of two types in Red and Green colour, as enclosed in Annexure-3. Display of Red Tag indicates incomplete scaffolds or any scaffold “Not Fit For Use”. Whereas the Green Tag indicates scaffold “Fit For Use”. Both the tags must be properly filled upand signed. The tags shall be of size 146 mm X 80 mm X 1mm thickness, made out of durable polyester laminated to resist water, grease and extreme atmospheric temperature with grommet. It shall be heavy-duty construction to withstand up to 36 kg of pull out force and displayed near access point ofscaffold. The sample of tags is enclosed as Annexure-III.

7.14 INCLEMENT WEATHER

Workers shall not work on scaffolds during storms or high winds. All working atheight at outdoors shall be discontinued at a wind velocity 65 KMPH (40 MPH)and during rain, thunderstorms or when there is likelihood of lightning.

7.15 LOAD ON SCAFFOLD PLATFORM

The recommended maximum distributed loading of scaffold platform shall confirm to the Table-1, given below.


RECOMMENDED MAXIMUM DISTRIBUTED LOADING OF SCAFFOLD P

TYPE OF NO. OF WORKING PLATFOR

SPACING OF WIDTH OF AREAPER

PERMISSIB MAX. LOAD

EXAMPLE OFMAX. LOAD

Light duty indep

MS18 ft2 15 lb/ft2 270 lb 1 man, hand

tools, patied Light duty indep

27 ft2 15 lb/ft2 405 lb plaster 2 man, handtools, pa

tied Medium duty indep

28 ft2 37 lb/ft2 1036 lb plaster. 1 man, mortaron spot board

tied Medium dutyindep

32 ft2 30 lb/ft2 960 lb and 130 bricks. 2 men and 620lb (280 Kg) of

tied Heavy duty indep

2 Headuty

24 ft 2 60 lb/ft2 1440 lb materials. 1 man, mortaron spot board

tied Heavy duty indep

2 light dut2 Headuty

27 ft 2 60 lb/ft2 1620 lb and 200 bric2 men and 1280 lb (58Kg) of

Heavy duty indep

2 Heavy duty

24 ft 2 37 lb/ft2 888 lb materials. 2 men and 550lb (250 Kg) of

tied 2 l24 ft 2 56 lb/ft2 1344 lb

materials. 1 man, mortaron spot board

32 ft2 37 lb/ft2 1184 lb and 180 bricks.1 man, mortaron spot board

Notes * Assumption made of board 9 inch. Weight of man 168 lb (76.2 Kg)

7

The procedure for erection for all scaffolds (low height as well as tall) shall be such that an unstable condition is not reached at any time. The ties and br

No portion of the scaffold shall be utilized unless that portion is fully decked, braced and tied. Warning notices shall be fixed to draw

During erection the scaffold erector must use full body safety harness(confirming and certified to IS: 3251/ EN: 361) with double fork type lanyard (confirming and certified to EN: 355). Safety harness shall always be used with

LATFORMS

SCAFFOLD

IN USE

STANDARDS PLATFORM * BAY

LE LOADING PER

BAY PER BAY **


endent 1 9 ft (2.7m) 3 boards

(1.67m2) (73 kg/m2) (122.4 kg) int,


(2.5 m2) (73 kg/m2) (183.7 kg) int,


(2.6 m2) (180 kg/m2) (469.8 kg)


(2.97 m2) (145 kg/m2) (453.4 kg)

endent vy

y

6 ft (1.8m) 5 boards (2.22 M2) (290 kg/m2) (653.0 kg)

ks.

endent tied

vy

2 light duty

6 ft (1.8m) 5 boards (2.5 M2) (290 kg/m2) (734.7 kg) 0

endent ight duty

6 ft (1.8m) 5 boards (2.22 M2) (180 kg/m2) (402.7 kg)

Put log 1 6 ft (1.8m) 5 boards (2.22 M2) (275 kg/m2) (609.5 kg)

Put log 1 8 ft (2.4m) 5 boards (2.97 m2) (180 kg/m2) (536.9 kg)

and 160 bricks

** Assumption made weight of spot board and mortar 70 lb (31.7 Kg) and weight of a brick 6 lb (2.72 Kg)

Table 1

.16 ERECTION

acing for the scaffold are to be erected simultaneously with other components.

attention to those partsof a scaffold, which are incomplete and not fit for use.

19

shock absorber (confirming and certified to EN-355). All time the scaffold erector/ helper should keep engaged their safety harness with a firm support orstable scaffold structure when on scaffold tube at a height of 2M and beyond. Suitable fall arrestor (Rope grab type confirming and certified to EN:353-2 andRetractable type fall arreste

7.1

During dismantling, no component, w

If dismantling has reached the stage at which a critical member has to beremoved, e.g. a tie or a brace, the stability of the structure shall be assured by fixing a similar or otherwise adequate

Because of the changes, which are made in a scaffold structure during its working life, it is not safe to assume that dismantling can be carried out in the reverse order of the erection. The scaffold, especially its ties a

If the scaffold is defective, it shall be repaired/ rectified before dismantling commences. Same personal fall protecm

The procedure of dismantling shall be orde

Scaffolds shall not be dismantled in vertical sections from one end towards the other, especially in cases where a hoist tower, which apparently gives support to the scaffold, is t

An access scaffold may have been temporarily stabilized during construction byrakers that have been subsequently removed. If the level of the lowest tie point is high, e.g. over entrance halls or above tall shop windows, temporary rakers,or other structurally adequate means of support, should be built up from the ground to achievre

r to EN –360) shall be used, wherever possible. Please refer Annexure-VIII.

7 DISMANTLING

hich endangers the stability of the remaining structure, shall be removed.

member in place lower down before the member to be taken out is removed.

nd bracing, shall be inspected for health and effectiveness prior to dismantling.

tion equipment shall be used asentioned in section 7.16 during erection.

rly and planned and shall proceed generally from the top horizontal sections.

o be left standing, unless special consideration is given to ties and bracings.

The following precautions shall be observed.

a) DO NOT remove all the ties.

b) DO NOT remove all the bracing first.

c) DO NOT remove all the intermediate and board end transoms.

d) DO NOT remove all intermediate guardrails.

e stability of the part-dismantled scaffold. For details of Rakerfer Figure 5.9.


During dismantling the persons engaged in job at a height of 2M or above mustuse full body safety harness with double fork type lanyard. Safety harness shall always be used with shock absorber. All time the persons shall keep engaged their safety harness with scaffold stricture when on scaffold tube at a height of2 M and above. Suitable fall arrestor shall be used, wherever possible. Forstandard of above PPE refer section 7.16. Refer Annexure-VIII.

7.18 LOWERING MATERIALS

Materials shall be lowered to the ground and not stored on the scaffold. In the case where a pavement is not to be obstructed and scaffolding materials have to be stored on the lowest lift awaiting collection, this lift should be stiffened and fully braced or propped by rakers, using materials recovered from the upperlifts.

Components shall not be thrown on the ground; they shall be lowered hand to hand in an orderly fashion or brought down by crane, gin wheel or othersuitable means.

7.19 PERSONAL FALL ARREST SYSTEMS

A. Where a complete guardrail system cannot be implemented, a personal fallarrest system (EN-364) shall be continuously used by anyone on an elevated work area or platform. A personal fall arrest system includes a full body s a f e t y harness (S: 3521, EN: 361), lanyard with shock absorber (EN:355), substantial anchorage(s), fall arrester (EN: 360, EN: 353-2), possibly a lifeline and safety net. Refer Annexure-VIII.

B. At no time shall Safety bel t be used as part of a personal fall arrest system.

C. Before each use, the user shall inspect all components of the personal fall arrest system he will be using.

D. Full body harnesses (including D-rings, EN-362), lanyards (including snaphooks, EN-362), lifelines, fall arrester and other components of personal fallarrest systems shall e i t he r be B I S o r EN ce r t i f i ed . Safety harnessshall be marked with either IS: 3521 or EN-361.

E. When used, personal fall arrest systems shall be attached by lanyard (EN:354) to a vertical lifeline, horizontal lifeline, or overhead structuralanchorage capable of supporting 2,000 kilograms.

F. Lanyards shall, if feasible, be tied-off to an anchorage point or lifeline that ishigh enough (preferably above shoulder height) to prevent the worker from free falling more than 6 feet (1.8 meters) or striking any lower level, should afall occur.

G. Lanyards shall have a maximum length of 1.8 meters (6 feet). Two or morelanyards may be connected together (hook to eye) provided the total possible free fall distance is not more than 1.8 meters (6 feet). However, self-retracting


lanyards (inertia reels) are preferred for these situations.

H. Locking type snap hooks or carabineers with self-closing, self-locking keepershall be attached to the end of each lanyard to prevent rollout. D-rings and snaphooks shall be compatible to prevent rollout.

I. When lifelines are used, they shall be fastened to fixed safe point(s) of anchorage capable of supporting 2,000 kilograms, shall be independent, and shall be protected from sharp edges and abrasion. Safe points ofanchorage may include structural members, but do not include guardrails, standpipes, vents, other small diameter piping systems, electrical conduit,outrigger beams, or counterweights.

J. Horizontal and vertical lifelines shall be made from 10 mm (3/8-inch) min.diameter wire rope. Other materials such as manila, nylon, or polypropylene rope shall not be used as a lifeline.

K. Horizontal lifelines shall be installed at the highest feasible point, preferably above shoulder height. Horizontal lifelines shall be maintained with sag at thecentre no greater than 300 mm (12 inches) for every 10 meters (33 feet) of lifeline length between attachment points.

L. Supervision shall ensure continuous monitoring of employees wearing a personal fall arrest system so that prompt assistance is possible in the event ofa fall.

M. Personal fall arrest system components shall not be used for any other purpose and shall not be re-used after stopping a fall or if any component hasany sign of damage.

7.20. STORAGE

The scaffold materials shall be stored properly, item wise separately. These shall be stacked in rack meant for the purpose, away from cement, lime, mortars, concrete, absorbent building material and damp condition. The scaffold pipes and boards may need inspection time-to-time and cleaning andpainting. No painting to be done for timber items.

8. TYPE OF SCAFFOLD

8.1 INDEPENDENT TIED SCAFFOLD

An independent tied scaffold (also known as double scaffold) is the mostcommon form of access scaffolding, which is classified into three subgroup:

• Light duty independent tied scaffold • Medium duty independent tied scaffold • Heavy-duty independent tied scaffold


Independent scaffold consists of a double row of standards connected togetherlongitudinally with ledgers and with transoms at right angles to the ledgers. Braces and ties are essential for its stability. Refer Figure. 7.1 and 7.2.

8.1.1 LIGHT DUTY INDEPENDENT TIED SCAFFOLD

a) GENERAL REQUIREMENTS

General construction requirements common to all scaffolds are given in Sec. 7.

b) DESIGN, LOADING AND DIMENSION

Single working platform shall be in use at any one time and the maximum distributed loading on the platform shall not exceed 15 lb/ft2 (73 kg/m2).Longitudinal distance between standard shall not exceed 9' (2.7 m). For general arrangement of scaffold refer Figure 7.1.

c) STANDARDS

The inner row of standards shall be placed as close as possible to the face of building or structure. However, to avoid projections in the building or structure, they may be placed 13" to 15" (325 mm-375 mm) away from the wall orstructure provided a single board is placed on the transom between the wall/structure and inner standard that should extend to within 2" (50 mm) of the face of the wall or structure. The outer row of standards shall be approximately3' 4" (1.0 m) from the inner row to allow for four boards.

d) LEDGERS

Ledgers shall be vertically spaced between 6' to 7' (1.8 to 2.1 m) centres. The first pair of ledger may be up to a maximum height of 8' 6" (2.6 m).

e) TRANSOMS

Transoms shall be placed on ledgers at 4’ (1.2.m) centre for 1½" (40 mm) boards. In each bay one transom shall be fixed to, or within 12" (300 mm) of, a standard with a load bearing coupler.

f) BRACING

Diagonal bracing (or ledger bracing ) at right angles to the structure at alternate pair of standards shall be provided for the full height of scaffold. These bracesshould be fixed to the ledgers close to the standard with swivel couplers.Longitudinal or facade bracing to the full height of scaffold, spaced not more than 100' (30 m) apart along scaffold length, shall be provided. Refer Figure 7.1.

g) TIES

To prevent movement of the scaffold either towards or away from the structure,it shall be securely tied to the structure throughout its entire length and height.


Ties should occur at every alternate lift and not more than 20' (6 m) interval along the scaffold.

h) DECKING

The working platform between the standards shall not be more than 36" (920 mm) wide, i.e. 4 boards each of 9" (230 mm) width.

i) LIMITATION

This scaffold can be used up to a maximum height of 200' (60 m).

8.1.2 MEDIUM DUTY INDEPENDENT TIED SCAFFOLD


General constructional requirements common to all scaffolds is given in Sec.7.0.

b) DESIGN, LOADING AND DIMENSION

Four working platforms may be used at any one time and maximum distributed load on each platform shall not exceed 37 lb/ft2 (180 kg/m2). Longitudinal distance between standards shall not exceed 7' (2.1 m). This distance may beincreased to 8' (2.4 m) if loading is less than 30 lb/ft2 (145 kg/m2). For general arrangement of scaffold refer Figure 7.2.

c) STANDARDS

The inner row of standards shall be placed as close as possible to the face of building or structure. However to avoid projections in the building or structure, they may be placed 13" to 15" (325 mm - 375 mm) away from the wall or structure provided a single board is placed on the transom that should extend to within 2" (50 mm) of the face of the wall or structure. The outer row of standards shall be approximately 3' 4" (1.0 m) from the inner row to allow for four boards or 4' 1" (1.24 m) for five boards with no inside board.

d) LEDGERS

Ledgers shall be vertically spaced between 6' to 7' (1.8 to 2.1 m) centres. Thefirst pair of ledger may be up to a maximum height of 8' 6" (2.6 m).

e) TRANSOMS

Transoms shall be placed on ledgers at 4' (1.2 m) centre for 1 ½" (40 mm) boards. In each bay one transom shall be fixed to, or within 12" (300 mm) of, a standard with a load bearing coupler.

f) BRACING


Diagonal bracing (or ledger bracing) at right angle to the structure at alternate pair of standards shall be provided for the full height of scaffold. These bracesshould be fixed to the ledgers close to the standards with right angle couplersor to the standards with swivel couplers. Longitudinal or facade bracing to the full height of scaffold spaced not more than 100' (30 m) apart along scaffold length, shall be provided.

g) TIES

To prevent movement of the scaffold either towards or away from the structure,it should be securely tied to the structure throughout its entire length and height. Ties should occur at every other lift and not more than 20' ( 6 m) interval along the scaffold.

h) DECKING

The working platforms between standards shall not be more than 3' 9" (1150 mm) wide i.e. five boards. One of these boards may be placed between inner row of standard and the building or structure.

i) LIMITATIONS


8.1.3 HEAVY DUTY INDEPENDENT TIED SCAFFOLD



b) DESIGN, LOADING AND DIMENSIONS

Maximum two working platforms shall be used at any one time and maximum distributed loading on each platform shall not exceed 60 lb/ft2 (290 kg/m2). Two additional platforms can be used for light duty access at a loading of 37 lb/ft2 (80 kg/m2) on each platform. Longitudinal distance between standard shall not exceed 6' (1.8 m). For general arrangement of scaffold refer Fig.7.2.

c) STANDARDS

The inner row of standards shall be placed as close as possible to the face of building or structure. However to avoid projections in the building or structure, they may be placed 13" to 15" (325 mm 375 mm) away from the wall or structure provided a single board is placed on the transom that shall extend to within 2" (50 mm) of the face of the wall or structure. The outer row of standards shall be approximately 4' 1" (1.24 m) from the inner row to allow for five boards or 4' 10" (1.47m) for six boards with no inside boards.

d) LEDGER


The vertical distance between each ledger or the first ledger and the base level on which standards are pitched (ground level ) shall not exceed 6' 6" (1.98 m).

e) TRANSOMS

Transoms shall be placed on ledgers at 4' (1.2 m) centre for 1½" (40 mm)boards. In each bay one transom shall be fixed to, or within 12" (300 mm) of, a standard with a load bearing coupler.

f) BRACING

Diagonal bracing (for ledger bracing) at right angle to the structure at alternate pair of standards shall be provided for the full height of scaffold. These bracesshould be fixed to the ledgers close to the standards with right angle couplersor to the standards with swivel couplers. Longitudinal or facade bracing to the full height of scaffold, spaced not more than 100' (30 m) apart along scaffold length, shall be provided.

g) TIES

To prevent movement of the scaffold either towards or away from the structure,it shall be securely tied to the structure throughout its entire length and height. Ties should occur at every other lift and not more than 20' (6 m) interval along the scaffold.

h) DECKING

The working platforms between standards shall not be more than 3' 9" (1150 mm) wide i.e. five boards and not more than 4' 6" (1380 m) i.e. six boards. One of these boards may be placed between inner row of standard and the building or structure.

i) LIMITATIONS


8.2 MOBILE TOWER SCAFFOLD

A mobile tower scaffold consists of four or more standards connected togetherlongitudinally with ledgers and with transoms at right angle to the ledger, forming a square or rectangular tower mounted on wheels. It has single working platform and is a common form of access scaffolding for painters and others who do work of a light nature and of short duration. Refer Figure 7.3,7.4, 7.5 and 7.6.


General construction requirements common to all Scaffolds are given in Sec. 7.0.



A mobile tower scaffold shall only have single working platform and the maximum distributed load (in addition to its own weight and the weight of the boards) shall be 30 lb/ft2 (145 kg/m2).

The height from floor or base of the tower to working platform of a mobile towerscaffold shall not exceed three times the minimum base dimension. In no case shall the minimum base dimensions be less than 4' (1.2 m) or more than 9’ (2.74 m)

c) FOUNDATION

A mobile tower scaffold shall only be used and moved on surfaces sufficientlyfirm and levelled to avoid instability.

d) STANDARDS

Joints in standards shall be made with end-to-end or parallel couplers.

e) LEDGERS AND TRANSOMS

The vertical spacing of ledgers and transoms shall not exceed 9' (2.74 m) or be greater than the minimum base dimension of the tower. The lowest ledgers and transoms shall be as near to the wheels as possible. Ledgers and transoms shall be secured to the standards by load-bearing couplers.

f) TIES/ RAKER

Normally mobile scaffolds are not tied, as it affects the mobility of tower. However if tie/ raker is used the height can be further increased.

Towers more than 32' (10 m) in height should be adequately tied to a building or structure. Where tying in to a building or structure is impracticable, rakers or guy wires at a slope of approximately 45 degrees connected to the tower at high level shall be used.

The strength of the guy wires shall be calculated giving due regard to the horizontal wind force and other known forces which will be applied to the tower.

g) DECKING

The single working platform of a mobile tower scaffold shall not project beyond the base area.

h) ACCESS

Provision of access using ladder should be from inside the structure. Where the means of access to the working platform is outside the structure, due consideration shall be given to the effect of such access on the stability of the tower.


i) OPERATION

Mobile tower scaffolds shall only be moved by pushing or pulling at the base. Force shall not be applied at a height greater than 4' 6" (1.37 m) above the floor level or base. No persons, equipment or materials shall be on the working platform or elsewhere on the structure whilst it is in motion. The wheel brakes shall be applied when the tower is in use.

k) LIMITATIONS

Mobile tower scaffolds erected and used in accordance with the foregoing direction, supported on four wheels and with not more than one working platform in use, may be used up to a maximum height of 40' (12 m). Mobile tower scaffolds departing from these directions shall be specially designed by a competent and qualified engineer.

8.3 BIRDCAGE SCAFFOLD

Birdcage scaffold is a general term applied to scaffolding erected in block form, and has a wide application. In its simplest form it is used for general access to ceilings and walls for light work. Generally scaffold consists of an arrangement of standards with ledgers and transoms supporting a closely boarded platform at the required level. Refer Figure 7.7.


General construction requirements common to all scaffolds are given in Sec. 7.0.


A birdcage scaffold shall only have a single working platform (closely boarded standards over the whole working area) in use at one time.

The maximum loading on this platform shall not exceed 15 lb/ft2 (73 kg/m2).

c) STANDARDS

Standards shall be set in rows at not more than 8' (2.438 m) centres.

d) LEDGERS

The ledger for the first lift may be fixed up to maximum height of 8' 6" (2.6 m)and the subsequent lifts should be between 6' 6" (1.98 m) and 8' (2.42 m) centres.

e) TRANSOMS

Transoms on all lifts except the top lift shall be secured to the standards with load-bearing couplers.


Transoms on the top lift and other working lifts for access to the walls may be secured to the ledger with right-angle of putlog couplers. These transoms should be at not more than 4' (1.2 m) centres and in each bay one shall be secured to, or within 12" (300 mm) of, a standard.

f) BRACING

Adequate diagonal bracing for the full height of the scaffold and at least to each corner of the structure in both directions shall be required to ensure stability.

g) TIES

All birdcage scaffolds be securely tied to surrounding walls throughout theirlength and height. Ties shall be affected by extending alternate ledgers and transoms on alternate lifts to bear against existing walls, or inserting separate tubes at the same intervals, and these shall be connected to the standards withload-bearing couplers. The ends of the tubes shall be packed where necessary to prevent damage to walls. Only load-bearing couplers shall be used forsecuring ties.

h) DECKING

The working platform shall be close-boarded over the whole working area.Where intermediate platforms are required for access to walls, decking,guardrails, toe boards, etc. shall be provided similar to that of light duty Independent Tied Scaffold (Refer Sec. 8.1.1).

i) GUARDRAILS AND TOEBOARDS

Unless the working platform ends within 6" (150 mm) of surrounding walls,guardrails and toe boards shall be provided.

k) LIMITATION

Birdcage scaffold erected in accordance with the foregoing directions with notmore than one working platform, may be used up to a maximum height of 200'(60 m) provided the scaffold is not subjected to wind or other external forces.

8.4 TRUSS SCAFFOLD

A truss (also known as cantilever or jib) scaffold is cantilevered out from a building or structure and used where it is impracticable to erect standardsbearing on the ground or other surface. It is a form of light independent tiedscaffold, which is entirely dependent upon the building or structure for supportand stability. Refer Figure7.8.


General construction requirements common to all scaffolds are given in Sec. 7.0.



Design, loading and dimensions shall be similar to that of a light independenttied scaffold with spacing and loading as specified in Sec. 8.1.1.b.

c) FOUNDATION

Before erection work begins, the building or structure shall be carefullyexamined to ensure that it is structurally sound enough to take the stressesinvolved in anchoring the scaffold.

d) INSIDE ANCHORAGE

The inside anchorage shall be wedged between two adjacent floors orhorizontal members of a building or structure by the use of adjustable base plates or reveal pins with timber sole plates and head plates. Sole plates and head plates shall run at right angles to floor and ceiling joints. Puncheonsshould be spaced at 4' 6" to 5' 6" (1.37 m to 1.524 m) centres and generally the spacing of the rows shall be 4' 6" (1.37 m).

e) CANTILEVER TUBES

Cantilever tubes (also known as needles and sometimes as transoms) shall besecured to the puncheons at right angles with load-bearing couplers and extend through an opening in the building or structure to support an independent tied scaffold on the outside. Two-way ties shall be secured to the cantilever tubes on either side of the opening with load-bearing couplers.

f) LEDGERS

Inner and outer ledgers shall be secured to the tops of the cantilever tubes with load-bearing couplers.

g) RAKERS

Rakers (One for every standard) shall be secured to an outside ledger above the opening and to an inside ledger at a lower level. The base of the raker shall bear (through a timber packing) on to a surface inside the building or structure, or on a ledger outside. Junctions between rakers and ledgers shall be secured with load-bearing couplers. The angle of rakers shall not be greater than 35 degrees from the vertical. Rakers more than 10' (3.0 m) in length shall be braced.

h) STANDARDS

Standards shall be secured to the ledgers as close as possible and to rakerswith load bearing couplers. The junctions shall be reinforced with check couplers.

i) BRACING


It is not always necessary for bracing to be fixed on the inside anchorage but where it is required it should be fixed with right angle or swivel couplers. No raker shall be longer than 10' (3.0 m).

k) FITTINGS

Diagonal braces may be secured to puncheons and standards with swivel couplers.

Intermediate transoms used to support the working platform may be secured to ledgers with putlog couplers.

All other fittings including those used on rakers, shall be load-bearing type. Check couplers shall be used immediately above junctions between standards and ledgers and immediately below junctions between rakers and ledgers.

Joints in braces shall be avoided where possible. If joints are necessary, parallel couplers shall be use. All other joints in tubing on truss scaffold shall be made with end-to-end couplers.

l) TIES

It is essential that a truss scaffold be securely tied to the building or structure with two-way, through or column box ties. Ties shall be positioned at everyalternate lift at not more than 20' (6.09 m) centres. Reveal ties shall not beused.

m) LIMITATIONS

Truss scaffolds erected in accordance with the foregoing directions, with not more than one working platform, may be used up to a maximum height of 40' (12.19 m) from truss to working platform.

8.5 INDEPENDENT SCAFFOLD

An independent scaffold is used to raise a working platform to the required height like Independent Tied Scaffold where providing ties with the structure for stability is not possible. Independent scaffold shall be erected in accordancewith Sec.7.0. construction common to all scaffolds and Sec. 8.1, IndependentTied Scaffold. Unlike Independent Tied Scaffold, Independent Scaffold is not tied to the structure for stability and therefore height of independent scaffoldshall not be more than 3 times its minimum base dimensions. Refer Figure.7.9.

8.6 TRESTLE SCAFFOLD

Trestle scaffold as a term applied to a working platform supported by trestles,split heads, folding steps, ladder, tripods or similar movable contrivances.

a) DESIGN, LOADING AND DIMENSIONS


A trestle scaffold shall only have a single working platform in use at one time. It is recommended that the maximum loading on the platform shall not exceed 15 lb/ft2 (73 kg/m2).

b) FOUNDATION

A trestle scaffold shall only be erected on a firm level surface with each stile or foot properly supported.

c) TRESTLES

c-1) PAINTER'S FOLDING TRESTLES

Hinges shall be checked to ensure that they are not broken, rusty or loose.Hinges should be of the self-locking type, which limits the angle to which the trestles can be opened (The angle of opening shall be 30 degree to 40 degree for aluminium and 24 degree to thirty six degree for timber). Timber trestlesshall be checked to ensure that they are not cracked or split, that cross bearers are through tenoned and double-wedged, and that check blocks and tie rodsare fitted (four on trestles up to 10' (3.05 m) and six on trestles over 10').Timber trestles should not be painted for visibility of defects.

c-2) STEEL EXTENDING TRESTLES

Trestles shall be checked to ensure that they are not twisted or damaged and that all four feet rest evenly on the ground. Adjustable cross-bars must besupported by purpose-made steel fixing pins which should be chained to the trestle to prevent loss.

d) DECKING

d-1) PAINTER'S FOLDING TRESTLES

Working platforms shall consist of at least two 9" (370 mm) scaffold boards placed side by side spanning horizontally between the trestles. Cross-bearers supporting the boards shall be not more than 5' (1.520 m) apart for 1½" (40 mm) boards and not more than 8' 6" (2.590 m) apart for 2" (51 mm) thick boards.

d-2) STEEL EXTENDING TRESTLES

Working platforms are normally four or five boards wide and shall conform to the requirements specified in Section 7.4.

e) GUARDRAILS AND TOEBOARDS

Guardrails and toe boards are not required on scaffolds, which are supported by folding trestles, split heads or similar devices, up to a height of 15' (4.572 m).

f) LIMITATIONS


Trestle scaffolds erected in accordance with the foregoing directions, with not more than one working platform, may be used up to a maximum height of 15' (4.572 m) from base to working platform. It shall be so located that a person working on the platform would not be liable to fall more than 15' (4.572 m).

8.7 SYSTEM SCAFFOLDING

System scaffolding is also known as unit or frame scaffolding and is composed wholly or partly of prefabricated section. There are many types of system scaffolding available which vary greatly in design and method of erection. Inspite of this wide variation the same basic principles described in Sec. 7.0. shall be applicable in this type also. It shall be erected by competent and experienced workmen. Care shall be taken that it is erected on a sound base with standards (or equivalent units) vertical and ledgers (or equivalent units)horizontal. It should be adequately braced and securely tied. Refer Figure 7.10& 7.11.

8.8 SLUNG SCAFFOLD

A slung scaffold is suspended by wire ropes or chains from roof or other structural members where scaffolding from the ground is impracticable. Generally, it is used for painting and other work of a light nature.




A slung scaffold shall only have a single working platform and the maximum distributed loading on the platform shall be taken as 15 lb/ft2 (73 kg/m2) with ledgers at 8' (2.438 m) centres and 24.5 lb/ft2 (120 kg/m2) with ledgers at 6' 6" (1.981 m) centres.

c) SUSPENSION

Working platforms may be suspended by chains, but wire ropes are more commonly used. Wire ropes should be at least 3.8" (9 mm) in diameter and conform to BS 302 (Steel Wire Ropes). The ¼" or 3 1/8" scaffold lashing must not be used as a means of suspension.

Wire ropes or chains shall be vertical and secured to ledgers as close as possible to transoms. Wire ropes should be secured by two full round turns and three bulldog grips (care being taken to ensure that the bulldog grips are fitted correctly). Chains shall be secured by shackles.

Where wire ropes pass round a sharp edged member, packing shall be provided to avoid high point loads and to prevent chafing. A working platform shall have at least six suspension points, evenly spaced, and kept taut. The


weight supported by a single wire rope shall not be greater than the safeworking load of the rope or of the member to which the rope is attached.

d) LEDGERS

Ledgers shall span the suspension points and be spaced at 6'6" (1.980 m) centres.

e) TRANSOMS

Transoms shall be secured on top of ledgers with load-bearing or putlog couplers at centres not exceeding 4' (1. 219 m).

f) DECKING

The working platform shall be close boarded over the whole working area and boards secured to prevent displacement. Work stages may be used as decking.

g) GUARDRAIL AND TOEBOARDS

Guardrails and toe boards shall be fitted at edges from which persons could fall a distance of more than 6' 6" (1.980 m). For exceptions see below.

Guardrails and toe boards are not needed on a platform suspended from roofmembers or a roof and used only for light work of short duration if there is adequate handhold at every working position and all material needed can be used safely in the absence of guardrails and toe boards.

h) TIES

The stability of the platform shall be ensured by securing adequate and suitable guy lines between the platform and suitable anchorage points. Guy lines shall be as near horizontal as possible and kept taut.

i) LIMITATIONS

Slung scaffolds erected in accordance with the forgoing directions may be used with single working platforms up to 8' by 8' (2. 438 m by 2.438 m) in area with men and materials spread evenly over the platform. Slung scaffolds departing from these directions, and those required for point loading, shall be speciallydesigned.

8.9 DROP SCAFFOLD

A drop scaffold is suspended by scaffold tubes from a roof, roof members, or other structural members where scaffolding from below is impracticable.Generally it is used for painting and other works of light nature. Refer Figure 7.13.



General construction requirements common to all scaffolds are given is Sec. 7.


Design, loading and dimensions for the type of drop scaffold shall be same aslight independent tied scaffold with spacing and loading as specified in Section 8.1.1. Design, loading and dimensions for the type of drop scaffold shall be same as that of slung scaffold with spacing and loading as specified in Section 8.8.

c) SUSPENSION

The outriggers on the type of drop scaffold shall be constructed of unit beamsor tube and fittings. Counterweights shall be securely fixed to the scaffolding and have a safety factor of three to one with the weight of the scaffolding, men and materials being taken into account.

For drop scaffold, check couplers shall be employed at the tops and bottoms of suspension tubes.

Wherever possible vertical suspension tubes shall be in one length. Where joints are necessary the tubes shall be single lapped using at least two couplers or shall be butted and lapped with a short length of tube. In the latter case, there shall be at least two couplers on each side of the lap.

d) LEDGERS, TRANSOMS, DECKING, GUARDRAILS & TOEBOARDS, TIES & LIMITATIONS

For drop scaffold the requirements shall be same as that of a Light Independent Tied Scaffold. Refer Section 8.1.1.

8.10 BRACKET (TANKBUILDER’S) SCAFFOLD

A scaffold supported by bracket straps welded to the tank wall. Upright brackets are hooked to the straps.

8.10.1Brackets and Straps

a) Brackets and bracket straps shall be constructed and erected in accordancewith the manufacturer’s instructions and this standard, using the minimum dimensions shown in Figure 7.12.

b) Bracket scaffolds shall only be used to support a Light-duty loading of 73 kg / sq.m.

c) Brackets, bracket straps and other associated structural members shall be freefrom detrimental corrosion, damage, or defects.

d) Bracket straps, welded to the tank wall, shall be at least 250 mm (10 inches)wide x 75 mm (3 inches) high x 10 mm (3/8-inch) thick, with bends at the centre for inserting brackets. The gap created by the bent section of the bracket


strap must be compatible in size with the bracket to be inserted, with a 3 mm (1/8-inch) maximum clearance on the front or back faces.

e) Bracket straps shall be welded to the tank shell for a length of at least 150mm (6 inches) along the top edge of the strap (two 75 mm welds min.) and down 25 mm (1 inch) along each side of the strap, with a 5 mm (3/16 inch)fillet weld. No weld is required along the bottom edge of the bracket straps.Refer Figure 7.12.

f) If 38 mm (1-1/2 inch) thick wood planks or equivalent steel boards are used, the maximum circumferential distance between brackets shall not be more than1.5 meters (5 feet) on centre.

g) Brackets shall be installed vertically.

h) Only certified welders shall weld bracket straps to the tank wall.

i) Prior to welding on any tank, approval of welding procedures and verificationof tank integrity is required from the Inspection Dept. of Refinery.

j) Prior to attaching the bracket, completed bracket strap welds shall beinspected and approved by a welding inspector who is certified by InspectionDept.

k) Brackets shall be inspected prior to installation by scaffold craftsmen and prior toeach use by scaffold users. Damaged or defective brackets shall be removed from service.

8.10.2Guardrails and Platforms for Bracket Scaffolds

a) A continuous guardrail system shall be provided along the outside platformedge.

b) A guardrail system shall be provided on the inside platform edge wherever the gap between the platform and the tank exceeds 360 mm (14 inches).

c) Guardrails for bracket scaffolds shall be constructed using either wire rope orsteel tubing. Wire rope guardrails shall be 10 mm (3/8-inch) diameter and shall be securely fixed and kept tight i.e., by the use of turnbuckles. Steel tubing shall meet the capacity requirements and there shall be no end-to-end connections occurring anywhere but at the guardrail support uprights.

d) Guardrail support uprights shall be made of scaffold grade tubing or structural angles. Preferably, these uprights shall be permanently welded to the brackets. However, an acceptable alternative is for each upright to be firmly secured intoa 150 mm (6-inch) minimum high sleeve or spigot pin, either of which is weldedto the bracket.

e) Guardrails and support uprights that are certified to meet OSHA 1925.450,Appendix A, Section 1(d) shall be used for bracket scaffolds.

f) Guardrail support uprights shall be constructed to such that the top rail is at least


0.95 meter (38 inches) and not more than 1.15 meters (45 inches) above the walking surface.

g) In addition to wearing hardhats, each person shall be provided with additional protection from falling objects through one or more of the following means:

• barricading the area below into which objects can fall and not permitting workers to enter the hazard area, or

• installing toe boards with or without screens, or

• erection of debris nets, catch platforms, or canopy structures sufficient tocatch falling objects.

h) Toe boards, where used, shall be installed as per Section 7.7. Toe boards shall not be nailed into scaffold planks.

i) All working levels shall be fully planked. Working levels shall be at least 2 planks but not more 3 planks wide.

j) Planks shall overlap in one direction only and the minimum overlap shall be 230 mm (9 inches).

k) Platform units and planks shall be secured to the brackets in a manner that will prevent movement.

l) The area below bracket scaffolds shall be barricaded and warning signs posted.

9. PORTABLE/ MOBILE LADDERS

The purpose of ladder in a scaffold shall provide safe access for and exit from a scaffold work platform and, not to carry out work at height.

Metal ladder shall be either of steel complying with IS1977 or aluminium alloy,comply with the suitable grade confirming to IS 617. Aluminium ladders and steps confirming to BS 2037 shall also be used.

The safety of ladders depends upon three important factors:

* The selection of the right ladder for the job to be done.

* The condition of the ladder.

* The safe use of the ladder.

9.1 SELECTION

a) A ladder shall be of the proper length for the job to be done. If it is used as a means of access or as a working place it shall rise to a height of at least 3' 6"(1.07 m) above the landing place or above the highest rung to be reached bythe feet of the person using the ladder.


b) Metal ladders, wooden ladders with metal reinforced stiles, and ladders, which are wet, shall not be used near electrical equipment with exposed live conductors.

c) Ladder shall have uniform spaced rungs (all rungs shall be the same distance apart), at a gap of 300 mm (12 inches) on centre.

d) Minimum distance between stiles of a straight ladder , or any section of an extension ladder, shall be 300 mm (12 inches), except for tripod ladder.

e) Ladders shall be examined for

i) cracked, damaged, buckled, warped or split stiles

ii) missing, broken, loose, decayed or damaged rungs, and splinters

iii) bent or missing hinges

Iv) shoe in feet, feet free from oily materials

iv) any other damage that hinders safe use of ladder.

No defective ladder shall be used. No painted ladder shall be used as this mayhide the defect. Refer Figure 6.1.

f) No one shall use makeshift or homemade ladders or carry out makeshiftrepairs to a damaged ladder.

9.2 POSITION / USE

a. All portable ladders shall be subjected to pre-use check after selection and certified before being put to use. The base supports of stiles of all ladders equally supported on a firm level surface. Boxes, blocks, barrels etc. shall not be used as a means of support.

b. Where a ladder is carried single-handed, the front end should be kept high enough to clear person's heads and special care taken at corners and blind sports.

c. The stiles of a ladder shall be equally supported on a firm level surface. Boxes, bricks, barrels, etc., shall not be used as a means of support and under no circumstances shall wedges or other loose material be used as packing.

d. Ladders shall not be supported on their rungs and rungs shall not be used to support scaffold boards.

e. The bottom rung of the ladder shall not be more than 600mm (2 feet) above the lower level used to mount the ladder.

f. The area at the base of a ladder shall be kept clear.


g. Ladders shall be set 1' (300 mm) out of each 4' (1.210 m) of height, i.e. at an angle of 75 degrees to the horizontal. Refer Fig.6.2. Or straight ladders and extension ladders may be supported vertically if both stiles of ladder are rigidly attached to a supporting structure at the top, middle and bottom of ladder, as isdone for mobile scaffold.

h. Ladder shall have clear perpendicular distance of 760 mm (30 inches) from the rungs to the nearest projecting object on the climbing side. When unavoidable obstructions are encountered, the minimum clearance distance may be reduced to 24 inches if deflector plates are provided.

i. The perpendicular distance from face of the rung on the climbing side to the nearest fixed object on the backside of the ladder shall not be less than 10 inches.

j. The minimum clearance to the nearest to the nearest fixed object shall be 13inches on each side of the centreline of single-rung ladder.

k. Ladders shall be set with metal reinforcing on the underside of rungs, and where reinforcing is provided on one side of stiles, that too shall be on the underside.

l. Where extension ladders are used fully extended, the minimum overlap of sections shall be four rungs. Splicing or lashing ladders together to obtain an extension shall not be permitted.

m. Both stiles of a ladder shall be evenly supported at the upper resting place andsecurely lashed to prevent any movement.

n. Where lashing at the upper resting place is impossible, measure must be taken to prevent movement of the ladder, by stationing a man at the foot but it mustbe borne in mind that a man stationed at the foot can only be expected to control a ladder up to 20' (6.10 m) in height. For proper lashing of ladder referFig.6.3.

o. Where there is a possibility of a ladder being struck by moving vehicles orplant, a man should be placed on guard or space at the base of the ladder fenced off. Similarly if a ladder is erected close to a door, the door should be locked shut or secured in the open position with a man on guard.

p. Ladder landing places or platforms are required at every 30' (9.140 m) of height and shall be provided with guardrails and toe boards. Holes in platforms through which ladders pass shall be as small as practicable.

q. Do not spice, lash or tie ladders or ladder sections together.

r. Tools and materials should not be carried by persons ascending or descending ladders except that tools may be carried in pockets or special belts, provided they do not impair movement.


s. A person working on or from a ladder must always have both feet on the rungsand a secure handhold. If the work to be done necessitates the use of bothhands, safety harness should be used. Only one person should be on a ladder at a time.

t. Before climbing a ladder, workers shall check that their safety shoes and the ladder are free from grease, oil and mud.

u. Rope grab fall arrester should be used while ascending/ descending ladder. Use personal fall arrest system (Safety harness with lanyard and shockabsorber, fall arresters etc.) for working on ladder beyond 1.8 M.

v. Work requiring lifting of heavy materials or substantial extension shall not be done from ladder.

w. Ladders shall not be moved, shifted or extended while occupied.

x. While climbing or descending, workers shall face the ladder and keep both hands on the ladder.

y. Ladder shall not be used in a horizontal position as platforms, walkways orscaffolds.

For further details on “Ladder Safety” Please refer standard on “Work At Height”.

10. 0 TEMPORARY STAIRWAYS

a) Stairways that are not be a permanent part of the structure on which constructionwork is being performed shall be at least 22 inches wide.

b) Temporary stairways shall have landings at not more than every 12 feet ofvertical rise. Such landings shall be at least 30 inches long, in the direction oftravel, and be at least 22 inches wide.

c) A guardrail system (such as guard rail, mid rail & toe board) shall beinstalled on open sides and edges of landings where a person could fall 6 feet or more.

d) Temporary stairways shall be installed between 30 degrees and 50 degreesabove the horizontal. A stair slope of between 30 and 35 degrees is preferred.

e) For temporary stairways, riser heights shall not exceed 8 inches or be less than 6 inches. Tread depths shall not exceed 11 inches or be less than 9 inches.

f) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. In any stairway system, variations in riser height and tread depth shall not be over6 mm (¼-inch).

g) Treads for temporary stairways shall be made of wood or other solid


material, and shall be installed the full width of the stair.

h) Temporary stairways having four or more risers, or rising more than 30 inches in height, whichever is less, shall have a sloping handrail and mid rail system on all open sides, or one (1) handrail on enclosed stairways on the right side descending.

i) The height of handrails for temporary stairways shall be 34” to 37” from theupper surface of the handrail to the surface of the tread, in line with the face of the riser at the forward edge of the tread. Mid rails shall be located at a heightmidway between the handrail and the stairway steps.

j) Handrails shall provide an adequate handhold for workers grasping them to avoid falling. A minimum clearance of 3 inches shall be provided between the handrail and wall or other object.

k) Handrails and the top rail of stair guardrail systems shall be capable ofwithstanding, without failure, a force of at least 90 kg (200 pounds) applied in any downward or horizontal direction at any point along the handrail or top rail.

l) Where doors or gates open directly on a stairway, a platform shall beprovided, and the swing of the door shall not reduce the effective width of theplatform to less than 20 inches.

m) All parts of stairways shall be free of hazardous projections, such as protruding nails or protruding handrails.

n) Stairs shall not be used if found wet and/ or slippery.

o) Spiral stairways are not permitted.

11. TRAINING

Training to scaffold supervisors, certifying engineer, scaffold erectors and employees working at height is a mandatory requirement. No one should workwith scaffold, unless exposed to specialised training on “Scaffold Safety”. For above, training shall be imparted once in 2 years and record shall be maintained. For scaffold supervisor (contractor supervisor) and certifyingengineer the course shall be at least of 1 day duration, for scaffold erecter ½ day and for persons working on scaffold – one class of 2 hours. The course content of training shall be as follows:

a) COURSE CONTENT FOR SCAFFOLD SUPERVISORS AND CERTIFYINGENGINEERS:

• Risk assessment for working at height. • Scaffold terminology • Scaffold standard, safe erection, dismantling of scaffold. Erection of safe work

platform for scaffold • General safety requirement, common to all scaffolds • Type of scaffold, advantage and limitation and safety features including safe

access to work platform. • Guard rail system, collective fall protection and personal fall protection system

with advantage and limitation.


• Selection, positioning, Inspection and use of portable ladder • Pre erection checklist, checklist and certification of scaffold, scaffold medical

certificate and Permit for “working at height”. • Demonstration on Sample scaffold at site. • Hands on exercise for use of Safety harness and different type of fall arresters.

Advantage and limitation of PPE.

b) COURSE CONTENT FOR SCAFFOLD ERECTERS:

• Hazards and risk during erection and dismantling of scaffold • Safe erection, dismantling of scaffold. Erection of safe work platform for

scaffold • Type of scaffolds and their safety features including safe access to work

platform. • Use of various fittings in scaffold, including their maintenance. • Important dos and Don’ts. • Guard rail system, collective fall protection and personal fall protection system

with advantage and limitation • Selection and positioning of portable ladder • Demonstration on Sample scaffold at site. • Hands on exercise for use of Safety harness and different type of fall arresters.


c) COURSE CONTENT FOR PERSONS WORKING ON SCAFFOLD:

• Hazards and risk while working on scaffold • Important dos and Don’ts. • Guard rail system, collective fall protection and personal fall protection system

with advantage and limitation • Safe use of portable ladder • Demonstration on Sample scaffold at site. • Hands on exercise for use of Safety harness and different type of fall arresters.


12. AUDIT OF SCAFFOLDS AND SYSTEM FOR WORK AT HEIGHT

The audit of scaffold and their system and procedures shall be carried out by a multi disciplinary team constituted by refinery management at least once in a year. The team may consist of members from Maintenance departments/ project dept./ E.S dept., Fire & Safety and Inspection Dept. At least one of them should have thorough knowledge of scaffolds, their system and procedure. The team must cover a shut down unit also. The checkpoint foraudit shall include following:

• Site visit and condition of scaffolds erected at site • Visit of storage for scaffold materials to check condition of storage and

materials • Check for compliance of “pre erection check for scaffold”, Scaffold inspection,

medical certification and working at height permit. • Training content for various categories of refinery as well as contractor

employees, training record, interview of trained persons to know the effectiveness of training

• Check for condition of PPE for “Fall Protection”.


13. REFERENCE

IS: 2482, IS: 1139, IS: 3629, IS: 4014 (Part I & II), IS: 3696 (Part-1&2), IS: 2750 BS: 1139, BS: 2482, BS: 5973 ANSI A 10.8 ANSI A 14.1 TO 14.5 ANSI Z 359.1 OSHA 1926, 450 to 452 OSHA 1926, 454 OSHA 1910.28 & 29 OSHA 1910, 159

OSHA 3150


ANNEXURE-I Format No. IOCL/Name of Refinery/WH/03

..….Refinery

PRE ERECTION CHECKLIST FOR SCAFFOLDS

(To be filled up and complied before erection of scaffold at site, before giving permit to start the erection)

Sl. No. ……….

Type of scaffold to be erected : Independent scaffold Independent tied scaffold Mobile scaffold Quick fix scaffold Birdcage scaffold Truss scaffold System scaffold Slung scaffold Drop scaffold Any other (specify)…………

A. Exact location of work: (Unit/ Area/ Equipment No.)………………………………………………………………………… ……………………………………………………………………………………………………………………………………….. B. Description of work to be performed…………………………………………………………………………………………. ……………………………………………………………………………………………………………………………………… C. Expected date and time to start erection………………………………… Expected date of completion…………………

D. Maximum No. of persons allowed on scaffold after erection :

E. Associated Permit : Hot Work / Vehicle entry Permit Cold Work Permit Confined Space Entry Permit Radiography Permit Excavation Permit Electrical isolation/ Energisation Permit Working at height Permit F. For the scaffold sufficient quantity of materials are available at site: S.N. Items Yes No Not

RequiredS.N. Items Yes No Not

Required 1. Scaffold pipes* X 2. Scaffold couplers * X 3. Deck boards* 4. Base plate* X 5. Sole plate 6. Toe board# 7. Reveal pin 8. Standard aluminum

ladder (as per IS/ BS)# 9. Mettle Wire to fix

ladder # 10. Tags (RED &

GREEN)* X

11. Toe board clip # 12. Joint pin 12. Approved full body

safety harness with lanyard/ life line **

13. Double fork type lanyard with energy absorber##

14. Fall arrester 15. Safety Net *- Compulsory for all scaffolds, used for working at height by persons. # Compulsory for scaffold of height 1.8 M and above. ## Compulsory during scaffold erection, repair, modification & dismantling and also when ladder is not in use. ** Compulsory for 2 M and above.

F. Name of trained scaffold erectors (Training validity- 1 years) S.N. Name Trained on S.N. Name Trained on 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. G. Name of trained scaffold supervisor (Training validity- 1 years) : 1…………………………..…. 2……………………………..


H. Quality of scaffold materials available at site: S.N. Items Yes No S.N. Items Yes No 1. Are scaffold tubes not damaged/

deformed? * 2. Are scaffold boards / sole plates

damaged/deformed? ** 3. Is couplers suitable type and free

from defects?4. Are base plates free from

defects?5. Are standard metal wires available

for tying ladder? 6. Are Standard alluminium ladder

(s) free from defects, deformity and temporary repairs.

*- Refer drawing no. **- Refer drawing no. Name and designation of site engineer / E-I-C: Signature with date

I. Safety check by issuer : S.N. Items Yes No Not

Required S.N. Items Yes No Not

Required 1. Area inspected for

erection of scaffold and found surface consolidated/ hardened X

2. is safety harness (s) with lanyards availableand in good condition?

3. Are other PPE such as fall arrester available?

4. Is Safety net available?

5. is 100% safety briefing given by Site engineer before start of work? X

6. Are scaffold materials properly stacked at site, without obstruction approach routs?

7. Are warning signs, barricading tapes available at site?

7. is medical certificate for persons working at a height of 2M and above available?

ISSUER (GSI) RECEIVER/EXECUTER (Site engineer)

Date…………………..Time ……………….

Signature:

Name…………………..Designation………..

Date…………………..Time ……………….

Signature:

Name…………………..Designation………..IMPORTANT NOTES: -This pre erection checklist shall be filled up by executer and issuer before start erection of each scaffold. -Pre-erection checklist shall be filled by E-I-C in duplicate and submit to issuer for further check. On further check by issuer, the executer shall comply with all requirements as mentioned in checklist and sign the checklist. - Duplicate copy shall be returned to issuer after compliance, whereas original shall be retained by executer.


Annexure-IIFormat No. IOCL/Name of Refinery/SS/02

________ REFINERYCHECK LIST FOR SCAFFOLD

UNIT LOCATION/ EQUIPMENT

DATE/ INSPECTED

TYPE OF SCAFFOLD

ERECTEREDBY

Item Checkpoint Condition Comments Action Foundation Firm and even Standards Vertical

Staggered joints Right spacing Not damaged

Ledgers Level Staggered joints Not loose Not damaged

Transoms Right spacing Not loose Right support

Bracing Ties None missing Not loose

Fittings Right fitting Not damaged Check couplers

Ladders Proper angle Right length Properly securedSeparate landingRight extension

Guardrails Right height Right length None missing

Toe-boards Others

General Comments

Contractor’s Supervisor/ Engineer Maintenance Engineer/ Civil/ Mechanical/ Instrument Engr.

Name Signature Date & Time

Scaffold shall be rechecked at a interval not exceeding seven days o just after any modification and repair or alteration and also after any adverse weather condition.

Above signatories must approve any change made to the scaffold after signing this check list.


ANNEXURE-III

TAGS TO CERTIFY SCAFFOLDS:

RED TAG (146mm X 80 mm X 1mm-thickness);- To be displayed by scaffold supervisorafter filling up the information on tag for all incomplete scaffold, scaffold under repair,alteration , inspection, due for certification etc. –Not fit for use.

GREEN TAG (146mm X 80 mm X 1mm-thickness);- To be displayed after filling upinformation and signing on tag. Display of tag indicates that scaffolds is “Fit for use”.

RED TAG GREEN TAG


ANNEXURE-IV

SCAFFOLD PIPES, BOARDS AND FITTINGS

Fig. 4.1: Scaffold Pipe


Fig. 4.2 Scaffold Fittings

Fig.4.3: Fixed Base plate (6” X 6”) Fig.4.4: Adjustable Base Plate SIGN. & STAMP OF TENDERER 49 of 104 2

Fig.4.5: Swivel Coupler and Sleeve Coupler

Fig.4.7: Sleeve/ End-to-End Coupler

Fig 4.6: Swivel Coupler


Fig.4.9: Right Angle (Double) Coupler

Fig.4.8: Putlog Coupler

Fig. 4.10: Joint Pin


Spigot

Spigot Pin

Standard

Standard

RING TYPE GIN WHEEL

HOOK TYPE GIN WHEEL

Mousing

Double Coupler

Fig.4.11: Bolted Spigot Fig.4.12: Gin Wheel

Fig.4.13: Reveal Pin


Metal Scaffold Plank

Fabricated Scaffold Deck Fabricated Scaffold Plank

Laminated Veneer Plank Solid Sawn Wood Plank

Fig.4.14 Scaffold Platform Unit



ANNEXURE-V SAFE ERECTION OF SCAFFOLDS:

5.1

1

BOARD BEARER (INTERMEDIATE

TRANSOM)

LEDGERS

(TRANSOMS)

LEDGER OR TRANSOM INSTALLED INSIDE STANDARD

(STANDARD)

BASE PLATES

SILLS (SOLE BOARDS) BASE LIFT

(KICKER LIFT)

Figure 5.2 SCAFFOLD TERMINOLOGY


2nd LIFT

2 Meters (6'-6") maximum lift height

2 Meters (6'-6") maximum lift height

6"

(STANDARDS) (LEDGERS) (TRANSOMS)

Figure 5.3 SCAFFOLD LIFTS


BFigure: 5.4


6

RIGHT-ANGLE (DOUBLE) COUPLERS (TYP.)

WALL OR SOLID STRUCTURE

TIMBER PACKING WALL OR SOLID STRUCTURE

TIE TUBES TO SCAFFOLD

Figure 5.5 PLAN VIEW OF TWO-WAY TIE


COLUMN



Figure 5.6 PLAN VIEW OF COLUMN BOX TIE


REVEAL PIN

WALL OR SOLID STRUCTURE

REVEAL TUBE WALL OR SOLID STRUCTURE

TIMBER PACKING


Figure 5.7 PLAN VIEW OF REVEAL TIE


RIGHT-ANGLE

5.8


ONLY ONE ADDITIONAL LIFT ALLOWED ABOVE RAKER TIE-IN POINT

RAKER TIE-IN POINT

SINGLE RAKER TUBE 6.4m (21ft.) MAX. LENGTH (NO SPLICES)

LONGITUDINAL STRUT TUBE

BASEPLATE SOLEBOARD

4

1 DETAIL SHORT BUTT TUBE

HORIZONTAL TIE TUBES (REQUIRED)

BASEPLATE

Figure 5.9 RAKER

ALTERNATIVE ON HARD GROUND


Figure 5.10 ONE MAN AND 20kg MAX. PER SQ. METER

MAX. TOTAL LOAD 73 KG PER SQ METER

11

Figure 5.11 TWO MEN AND 40kg MAX. PER SQ. METER

MAX. TOTAL LOAD 180 KG PER SQ METER


SAND OR ASPHALT SURFACE

TIMBER SILLS (SOLE BOARDS) REQUIRED (NOT PLANKS)

Figure 5.12 GROUND SUPPORT

BASE LIFT 2/3 OF THREAD LENGTH MAXIMUM

TOTAL THREAD LENGTH

TOTAL JACK HEIGHT

Figure 5.13 BUSE OF ADJUSTABLE BASE PLATE


CHECK PLUMB BOTH SIDES OF SLEEVE COUPLER

END-TO-END (SLEEVE)COUPLER

POST (STANDARD)

Figure 5.14A BEND-TO-END COUPLER JINING

STANDARDS


Fig. 5.14 B: PLUMNESS


5.15

POSTS (STANDARDS)

BEARER (TRANSOM)

RUNNER (LEDGER)

BOARD BEARER (INTERMEDIATE TRANSOM)

IF NEEDED BEARER

50mm (2") THK.

(TRANSOM)

Figure 5.16 SUPPORT SPACING FOR PLANKS (BOARDS)

50mm (2") THICK


EACH END OF PLANKS (BOARDS) UP TO 1.8m (6 Ft.) LONG FIXED TO A SUPPORT

FIXED FIXED

LADDER ACCESS OPENING

FIXED

WIRE LASHING WRAPPED AROUND PLANK (BOARD) ENDS AND TUBES

Figure 5.17 SECURING PLANKS


300mm 150mm (6") MIN. (UNLESS CLEATED)(12") MIN. 300mm (12") MAX.

OVERLAP BEARER OVERHANG

BOARD BEARER (INTERMEDIATE TRANSOM)

(TRANSOM)

Figure 5.18 PLANK OVERLAP AND OVERHANG

RUNNER (LEDGER)

POST (STANDARD)


BEARER (TRANSOM)

NODE POINT (TYP.)

300mm (12") Max. (Typ.)

3rd LIFT

POST (STANDARD)

2nd LIFT

ADJUSTABLE (SWIVEL) COUPLER

(TYP.) 1st LIFT

35 - 550 0

(TYP.) 6"

BASE LIFT

Figure 5.19 TRANSVERSE (SECTIONAL) "ZIG-ZAG" BRACING

TUBE AND COUPLER SCAFFOLD



(TYP.) 300mm (12") Max. (Typ.)

POST (STANDARD)

BEARER (TRANSOM)

NODE POINT (TYP.)

RUNNER (LEDGER)

NODE POINT (TYP.) POST

(STANDARD)

3rd LIFT

SEE TYP. DETAIL

BEARER (TRANSOM)

2nd LIFT

1st LIFT

35 - 550 0

(TYP.)

6" MAX. 3 OPEN BAYS

BASE LIFT

Figure 5.20 TRANSVERSE (SECTIONAL) "ZIG-ZAG" BRACING



BEARER (TRANSOM)


(TYP.)

NODE POINT (TYP.)

3rd LIFT

300mm (12") Max. (Typ.)

POST (STANDARD)

2nd LIFT

1st LIFT

35 - 550 0

(TYP.) 6"

BASE LIFT

Figure 5.21 TRANSVERSE (SECTIONAL) "X" BRACING



5.22


JOINTS IN ADJACENT POSTS (STANDARDS) NOT IN SAME LIFT HEIGHT

JOINTS IN ADJACENT RUNNERS (LEDGERS) NOT IN SAME BAY

Figure 5.23 SCAFFOLD JOINTS


BFigure 5.24: Work Platform

29 SIGN. & STAMP OF TENDERER 74 of 104

BFigure 5.25: Access to Work Platform

BFigure 5.26: Ladder Access Tower


TRANSOM OR LEDGER

ADJUSTABLE (SWIVEL) COUPLERS (4 each)

300mm 300mm (12") Min. (12") Min.

BFigure 5.27 Transom or Ledger Spice SIGN. & STAMP OF TENDERER 76 of 104 31

ANNEXURE-VI

INSPECTION OF LADDER:

STILES DO NOT

CHECK FOR CRACK/WEAR

CHECK FOR WARPING, CRACKS, SPLINTERS,

RUNGS DO

DENTS

TWIST

NOT TURN

TAG DEFECTIVE LADDERS

STILES DO NOT PULL APART

Figure 6.1 LADDER INSPECTION


0.90 m (3 Ft.)Minimum

Figure 6.2 LADDER POSITION


Fig. 6.3. Fixing of Ladder


INSPECTION OF SCAFFOLD TUBES:

FLAME CUT TUBE SPLIT

EEND TUBSPLIT END TUBE

CROSS CUT TUBE

MUSHROOM HEADED TUBE

BENT TUBE

WELDED TUBE

FIGURE 6.4 DAMAGED

TUBES


Figure 6.5 PLANK INSPECTION


SPLIT WORN

WARPED TWISTED

BROKEN DAMAGED HOOP IRON

Figure 6.6 PLANK INSPECTION

6

Figure6.7 UNSAFE FOUNDATIONS


Fig. 6.8. Inadequate Material Guard


BANNEXURE-VII

TYPE OF SCAFFOLDS:

FIG.7.1- VIEW OF INDEPENDENT TIED SCAFFOLD


OINT

FIG.7.2- ANOTHER VIEW OF INDEPENDENT TIED SCAFFOLD


TIMBER COVER FOR ACCESS HOLE (OR HINGED)

TOPRAIL MIDRAIL

TOEBOARD

PLAN BRACE UNDER DECK

PLAN BRACE

WIRE LASHING (TOP, MIDDLE AND BOTTOM OF LADDER)

LADDER SHOULD BE FIXED TO NARROWER WIDTH OF TOWER

TRANSVERSE (LEDGER) BRACING

LOCKING CASTERS

PLAN BRACE BOTTOM OF LADDER SUPPORTED

Figure 7.3 MOBILE SCAFFOLD (INTERNAL LADDER)


SIGN. & STAMP OF TENDERER

Fig.-7.4

87 of 104 4

5

Figure 7.5 FABRICATED TUBULAR FRAME

MOBILE SCAFFOLD

GUARDRAIL SYSTEM (TOPRAIL, MIDRAIL, TOEBOARD) ACCESS GATE

WORKING PLATFORM

END FRAME TOEBOARD

LOCKING PINS

SCISSOR (CROSS) BRACING ACCESS LADDER

PLAN BRACE CASTER FASTENING PINS

LOCKING CASTERS


INSERT SHAFT HOLE FOR FASTENING PIN

SWIVEL LOCKING ASSEMBLY

Figure 7.6 MOBILE SCAFFOLD CASTER


FIG.7.7 BIRDCAGE SCAFFOLD


FIG.7.8- TRUSS SCAFFOLD


COVER OR GUARDRAILS AROUND ACCESS HOLE NOT SHOWN

TOPRAIL

MIDRAIL

TOEBOARD

PLAN BRACE UNDER DECK

TRANSOM PLAN BRACE

WIRE LASHING

RUNNER (LEDGER)

LADDER SHOULD BE FIXED TO NARROWER WIDTH OF TOWER

POST (STANDARD)

TRANSVERSE (LEDGER) BRACING

BASE PLATE

PLAN BRACE BOTTOM OF LADDER

SUPPORTED BY TRANSOM SILLS

(SOLE BOARDS) BASE PLATE ( TYP. )

Figure 7.9 INDEPENDENT SCAFFOLD

(ALSO CALLED TOWER SCAFFOLD)


TYPICAL SYSTEM SCAFFOLD BASE IN THE PROCESS OF BEING ASSEMBLED AND LEVELLED

TYPICAL SYSTEM SCAFFOLD BEING ASSEMBLED

Figure 7.10 SYSTEM SCAFFOLD ERECTION


VARIOUS INDUSTRY JOINT CONNECTIONS

GUARDRAIL SYSTEM

TOEBOARD

STAIR UNIT

WORKING LEVEL

POSTS (STANDARDS)

RUNNERS (LEDGERS)

BEARERS (TRANSOMS)

SILL (SOLE BOARD)

DIAGONAL BRACES

VARIOUS INDUSTRY JOINT CONNECTIONS

Figure 7.11 TYPICAL SYSTEM SCAFFOLD

96 of 104SIGN. & STAMP OF TENDERER 13

TANK SHELL

TOPRAIL (STEEL TUBING OR 3/8" DIA. WIRE ROPE)

MIDRAIL (STEEL TUBING OR 3/8" DIA. WIRE ROPE)

HOOKED OVER TO BRACKET STRAP FORM SUPPORT

BRACKET STRAP

BRACKET SPACER

PLANKS (BOARDS)

TOEBOARD

BRACKET (TANK BUILDER'S) SCAFFOLD

DEPTH 5mm (3/16") FILLET WELD TO TANK SHELL

25mm (1") MAX.SIDE WELDS WIRE ROPE

FIXING HOLE

GUARDRAIL SUPPORT UPRIGHT

75mm (3") min.

10mm (3/8")THK. (min.) STEEL PLATE

BRACKET STRAP DETAIL

ANCHOR PLATE

PERMANENTLY WELDED OR SECURED TO PERMANENTLY WELDED 150mm (6") HIGH SLEEVE OR INTERNAL SPIGOT/PIN

SPACER

ANGLE STEEL

BRACKET

Figure 7.12 BRACKET SCAFFOLD



BFigure : 7.13. Suspended Scaffold

15

ANNEXURE-VIIIPERSONAL PROTECTIVE EQUIPMENT

Fig. 8.1A. Safety HarnessFig.8.1 B. Safety Harness

Fig. 8.2. Double Lanyard with Snap Hooks & Shock Absorber


Fig.8.3: Rope Grab Type Fall Arrester Fig.8.4 : Retractable Type Fall Arresters


Annexure-IX

Format No. IOCL/Nam of Refinery/WH/01 INDIAN OIL CORPORATION LIMITED

Sl. No.___________ REFINERY

PERMIT FOR WORKING AT HEIGHT

(REQUIRED FOR WORKING AT HEIGHTS OF 2.0 METERS & ABOVE) This permit authorizes for provision of safe access / platform/ working

arrangement at height for carrying out the job. In addition depending on nature of work, separate work permit must be obtained.

FROM : _____ HRS DATE_________ TO ______ HRS DATE________

NAME OF THE AGENCY / CONTRACTOR……………………………………………………………. NAME OF THE SITE SUPERVISOR…………………………………………………………………… JOB/WORK ORDER NO__________________LOCATION OF WORK ___________________ DESCRIPTION OF WORK ______________________________________________________ TOTAL NO. OF WORKERS ALLOWED __________________________________________

PERMITTEE SHALL CHECK THE FOLLOWING ITEMS FOR COMPLIANCE BEFORE SOLICITING THE PERMISSION.

YES NOT REQ 1. Have scaffolds been checked and certified in prescribed form by scaffold supervisor?

2. Have scaffolds been tagged with green card duly filled and signed by scaffold supervisor?

3. Is scaffold rechecked and re-certified weekly?

4. Is scaffold erected on firm ground and sole plate & base plate have been used?

5. Is the hanging baskets used of proper construction, tested and certified for the purpose.

6. Is the work platform made free of hazards of all traps/ trips/ slips & fall?

7. Have cat ladders, crawling boards etc been used for safe working at sloping roof

8. Has edge protection provided against fall from roof/ elevated space?

THE FOLLOWING ITEMS SHALL BE CHECKED FOR RISK ASSESMENT BY ISSUER AND COMPLIED BY PERMITTEE BEFORE SOLICITING THE PERMISSION.

9. Is the platforms been provided with Toe board, guardrail & area below is barricaded.

10. Checked whether safety harness & necessary arrangement for tying the life-line,

fall arresters etc provided to the worker for working at height.

11. Have precaution been listed below for safe working at height for source of energy

Such as electricity

11 Is proper means of access to the scaffold including use of standard aluminum ladder

provided ?

12. Is the raised work surface properly illuminated?

13. Is the workers are working near unguarded shafts, excavations or hot line?

14. Checked for provision of collective fall protection such as safety net


____________________________________________________________________________

____________________________________________________________________________

____________________________________________________________________________

15. Additional PPE recommended

ADDITIONAL PRECAUTION REQUIRED, IF ANY

Fire Permit Signatory /Gas Safety Inspector Permittee/ Receiver (Issuer)

Signature __________________________ Signature _______________________________ Name _____________________________ Name ___________________________________ Desig. ______________ Tel No. ________ Desig. ___________________ Tel No. ________

Concerned Area HOD/RSM ** Permittee HOD ** Signature & Date _____________________ Signature & Date ____________________

** Required in case: Permit is needed beyond normal working hours (8.00 Hrs to 17.00 Hrs.)/ round the clock/ Sundays & holidays.

Closing of the work permit: Receiver : Certified that the subject work has been completed / stopped and area cleared

Issuer: Verified that the job has been completed and area cleared and is safe from any hazard.

Date & Time Name & Designation

Signature Date & Time Name & Designation

Signature

Clearance Renewal:

Date Time Additional

precaution s if any, Otherwise mention “NIL”

Issuer Receiver

From To Name of GSI / FPS

Desig. of GSI / FPS

Signature of GSI / FPS

Name of Permittee

Desig. of Permittee

Signature of Permittee


INSTUCTIONS: -1. This permit will be issued in Triplicate. GREEN COPY (ORIGINAL) and WHITE COPY

(TRIPLICATE) will be for the Permittee. ISSUING AUTHORITY will retain WHITE COPY (DUPLICATE). This permit shall be valid for a period of 8 hours only, unless it is renewed/ extended. This clearance on the same permit can be renewed/ extended up to a maximum of seven calendar days.

2. After the completion of the job, copies of work permit should be returned to the ISSUER. 3. Items applicable must be ticked (√). 4. All works at height shall be discontinued during rain/ high wind/ floods. 5. Stop all jobs in case scaffold is sagging unduly. Report to EIC. 6. Metallic tubular scaffolding and standard aluminium ladders are only to be used. 7. All works must stop on instruction from permit issuing authority, permittee and officers of F&S

Dept. or whenever unsafe condition is detected. 8. Permittee shall obtain permission from the respective disciplines. 9. Permittee to ensure the compliance of safety precaution required mentioned in permit 10.Use of approved type full body safety harness along with lifeline is must for working at height of

2.0 M and above. 11.Permit must be available at site during the work. 12.Use of safety helmet and shoe is mandatory for all work sites. 13.Permittee shall ensure that all working personnel have taken SAFETY TRAINING before start of

work. Toolbox talk and key point tipping shall be given by permittee daily before start of work. 14.Sketches should be provided, if required.


_______________________

ANNEXURE

Format No.-IOCL/Name of Refinery/WH/04 MEDICAL CERTIFICATE

Form for Medical Check Up for the Workman engaged by the Contractor (Working at Heights)

Certified that I ___________________ have examined Shri ____________________Age _________ who has signed below in my presence. The details of his examination as required are given in the enclosed medical examination report. I certify that all clinical and pathological tests were done in my hospital/dispensary under my instructions and I find him fit. General and physical examinations of Shri ________________ do not reveal any abnormality. He does not suffer from any acute / chronic skin disease or any contagious or infectious disease. He is medically fit to work at height of 2.0 meters and more since he is free from Vertigo, Epilepsy or Fits, general giddiness and height related disease. His B.P., Pulse, Eye sight etc. are normal. In my opinion Shri ____________________ is physically and mentally fit for job in _____________

Signature of the workmen Date: _____________________________

Signature and Rubber stamp of medical practitioner with name

Note: This certificate is to be given on the letter head of the registered medical practitioner who ispossessing allopathic qualification as recognized by the Indian medical council. Below the signature,the rubber stamp of the medical practitioner should be affixed. Te letterhead normally should contain the following:

1) Name of the Medical practitioner: 2) Qualifications: 3) Registration Number: 4) Designation: 4) Address:


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