Ventilation. Dust hazards created by abrasive blasting v How respirable dust is formed v Composition...
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Transcript of Ventilation. Dust hazards created by abrasive blasting v How respirable dust is formed v Composition...
VentilationVentilation
Dust hazards created by Dust hazards created by abrasive blastingabrasive blasting
How respirable dust is formedHow respirable dust is formed
Composition and toxicityComposition and toxicity
Review exposure limits in 29 CFR Review exposure limits in 29 CFR 1910.10001910.1000
1a
Dust hazards created by Dust hazards created by abrasive blastingabrasive blasting
Organic abrasivesOrganic abrasives
Flammable or explosive dustFlammable or explosive dust
1b
Blast-cleaning enclosuresBlast-cleaning enclosures
Exhaust ventilationExhaust ventilation
Baffling air inlets and access Baffling air inlets and access openingsopenings
Rate of exhaustRate of exhaust
2a
Blast-cleaning enclosuresBlast-cleaning enclosures
Before opening:Before opening:• blast must be turned offblast must be turned off• exhaust system must be runexhaust system must be run
Protection for observation windowsProtection for observation windows
Slit abrasive-resistant bafflesSlit abrasive-resistant baffles
2b
Blast-cleaning enclosuresBlast-cleaning enclosures
DoorsDoors• must be flanged and tight when must be flanged and tight when
closedclosed• must be operable from both inside must be operable from both inside
and outsideand outside
2c
Inspection & maintenance of Inspection & maintenance of exhaust systemsexhaust systems
Z9.2-1960, and ANSI Z33.1-1961Z9.2-1960, and ANSI Z33.1-1961
Dust leaks must be repaired ASAPDust leaks must be repaired ASAP
Static pressure drop at the exhaust Static pressure drop at the exhaust ductsducts
3a
Inspection & maintenance of Inspection & maintenance of exhaust systemsexhaust systems
Installations where the abrasive is Installations where the abrasive is recirculatedrecirculated
Dust collectorsDust collectors
3b
Personal Protective Personal Protective EquipmentEquipment
Abrasive-blasting respirators must Abrasive-blasting respirators must be worn:be worn:• inside blast cleaning roomsinside blast cleaning rooms• when using silica sandwhen using silica sand• when toxic dust exceeds when toxic dust exceeds
exposure limitsexposure limits
Dust filter respiratorsDust filter respirators
4a
Personal Protective Personal Protective EquipmentEquipment
Heavy canvas or leather gloves Heavy canvas or leather gloves and apronsand aprons
Safety shoesSafety shoes
Eye and face Eye and face protectionprotection
4b
Air quality for abrasive-Air quality for abrasive-blasting respiratorsblasting respirators
Free of harmful quantities of dusts, Free of harmful quantities of dusts, mists, or noxious gasesmists, or noxious gases
Meets requirements in 29 CFR Meets requirements in 29 CFR 1910.134(i)1910.134(i)
5a
Operating procedures and Operating procedures and general safetygeneral safety
Dust must not accumulate on the floor or ledges outside of an abrasive-blasting enclosure
Dust spills must be cleaned up promptly
Keep aisles and walkways clear
6a
Grinding, polishing, and Grinding, polishing, and buffing operationsbuffing operations
Local exhaust ventilation systemsLocal exhaust ventilation systems• Remove dust, dirt, fumes, and gasesRemove dust, dirt, fumes, and gases• Required when employee exposure Required when employee exposure
exceeds permissible exposure limitsexceeds permissible exposure limits
7a
Grinding, polishing, and Grinding, polishing, and buffing operations buffing operations
Hood and branch pipe Hood and branch pipe requirementsrequirements• Design and placement so particles fall Design and placement so particles fall
or are projected into the hoodsor are projected into the hoods• Operation must not cause particles to Operation must not cause particles to
be thrown into the operators be thrown into the operators breathing zonebreathing zone
• Follow specified exhaust volumesFollow specified exhaust volumes
8a
Grinding, polishing, and Grinding, polishing, and buffing operationsbuffing operations
Exhaust system requirementsExhaust system requirements• Designed and tested in accordance Designed and tested in accordance
with American Standard with American Standard Fundamentals Governing the Design Fundamentals Governing the Design and Operation of Local Exhaust and Operation of Local Exhaust Systems, Z9.2-1960Systems, Z9.2-1960
• All exhaust systems must be provided All exhaust systems must be provided with suitable dust collectorswith suitable dust collectors
9a
Hood and enclosure Hood and enclosure designdesign
Functions to:Functions to:• Protect the operator from the hazards Protect the operator from the hazards
of bursting wheels, andof bursting wheels, and• Provide a means for the removal of Provide a means for the removal of
dust and dirt generated dust and dirt generated
Structural strength Structural strength
10a
Hood and enclosure Hood and enclosure designdesign
Adaptable to particular machineAdaptable to particular machine
Exhaust hoods for floor stands, Exhaust hoods for floor stands, pedestals, and bench grinders pedestals, and bench grinders must be designed in accordance must be designed in accordance with figure G-2 of 1910.94(b)with figure G-2 of 1910.94(b)
10b
Hood and enclosure Hood and enclosure designdesign
Swing-frame grinders must be Swing-frame grinders must be provided with exhaust booths as provided with exhaust booths as indicated in figure G-3 of indicated in figure G-3 of 1910.94(b)1910.94(b)
10c
Hood and enclosure Hood and enclosure designdesign
Portable grinding operations, Portable grinding operations, whenever the nature of the work whenever the nature of the work permits, must be conducted within permits, must be conducted within a a partial enclosurepartial enclosure
10d
Hood and enclosure Hood and enclosure designdesign
Hoods for polishing and buffing Hoods for polishing and buffing and scratch-brush wheels must be and scratch-brush wheels must be constructed to conform as closely constructed to conform as closely to figure G-4 of 1910.94(b) as the to figure G-4 of 1910.94(b) as the nature of the work will permitnature of the work will permit
10e
Hood and enclosure Hood and enclosure designdesign
Cradle grinding and polishing Cradle grinding and polishing operations must be performed operations must be performed within a partial enclosure similar to within a partial enclosure similar to figure G-5 of 1910.94(b)figure G-5 of 1910.94(b)
10f
Hood and enclosure Hood and enclosure designdesign
Hoods for horizontal single-spindle Hoods for horizontal single-spindle disc grinders must be constructed disc grinders must be constructed to conform as closely as possible to conform as closely as possible to the hood shown in figure G-6 of to the hood shown in figure G-6 of 1910.94(b)1910.94(b)
10g
Hood and enclosure Hood and enclosure designdesign
Horizontal double-spindle disc Horizontal double-spindle disc grinders must have a hood grinders must have a hood encircling the wheels and grinding encircling the wheels and grinding chamber similar to that illustrated chamber similar to that illustrated in figure G-7 of 1910.94(b)in figure G-7 of 1910.94(b)
10h
Hood and enclosure Hood and enclosure designdesign
Vertical-spindle disc grinders must Vertical-spindle disc grinders must be encircled with a hood so be encircled with a hood so constructed thatconstructed that• the heavy dust is drawn off a surface the heavy dust is drawn off a surface
of the discof the disc• the lighter dust exhausted through a the lighter dust exhausted through a
continuous slot at the top of the hood continuous slot at the top of the hood as shown in figure G-1 of 1910.94(b)as shown in figure G-1 of 1910.94(b)
10i
Hood and enclosure Hood and enclosure designdesign
Grinding and polishing belt hoodsGrinding and polishing belt hoods• must be constructed as close to the must be constructed as close to the
operation as possibleoperation as possible• the hood should extend almost to the the hood should extend almost to the
beltbelt• one-inch wide openings are provided one-inch wide openings are provided
on either sideon either side
10j
Operations considered to Operations considered to be spray finishingbe spray finishing
Methods wherein organic or Methods wherein organic or inorganic materials are utilized in inorganic materials are utilized in dispersed form for deposit on dispersed form for deposit on surfaces to be coated, treated, or surfaces to be coated, treated, or cleanedcleaned
May involve either automatic, May involve either automatic, manual, or electrostatic depositionmanual, or electrostatic deposition
11a
Operations considered to Operations considered to be spray finishingbe spray finishing
Does not include:Does not include:• metal spraying or metallizingmetal spraying or metallizing• dippingdipping• flow coatingflow coating• roller coatingroller coating• tumblingtumbling• centrifugingcentrifuging• spray washing and degreasing systemsspray washing and degreasing systems
11b
Location and use of spray Location and use of spray boothsbooths
Enclose or confine all operationsEnclose or confine all operations
12a
Must be located as provided in Must be located as provided in sections 201 through 206 of the sections 201 through 206 of the Standard for Spray Finishing Using Standard for Spray Finishing Using Flammable and Combustible Flammable and Combustible Materials, NFPA No. 33-1969Materials, NFPA No. 33-1969
Location and use of spray Location and use of spray boothsbooths
12b
Location and use of spray Location and use of spray boothsbooths
Used to enclose or confine all Used to enclose or confine all spray finishing operations covered spray finishing operations covered by 29 CFR 1910.94by 29 CFR 1910.94
TermsTerms• Spray boothSpray booth• Spray roomSpray room
12c
Design and construction of Design and construction of spray boothsspray booths
29 CFR 1910.107(b)(1)-(4) and (6)-29 CFR 1910.107(b)(1)-(4) and (6)-(10)(10)
ANSI ANSI Z9.2-1960Z9.2-1960
13a
Design and construction of Design and construction of spray boothsspray booths
Lights, motors, electrical equipment, Lights, motors, electrical equipment, and other sources of ignition must and other sources of ignition must conform to the requirements of 29 conform to the requirements of 29 CFR 1910.107(b)(10) and (c)CFR 1910.107(b)(10) and (c)
In no case must combustible material In no case must combustible material be used in the constructionbe used in the construction
13b
Design and construction of Design and construction of spray boothsspray booths
WalkwaysWalkways
Baffles, distribution plates and dry-Baffles, distribution plates and dry-type overspray collectorstype overspray collectors
Wet or water wash spray boothsWet or water wash spray booths
13c
Design and construction of Design and construction of spray boothsspray booths
Collecting tanksCollecting tanks
Pump manifolds, risers, and Pump manifolds, risers, and headersheaders
13d
Design and construction of Design and construction of spray roomsspray rooms
Must be constructed of masonry, Must be constructed of masonry, concrete, or other noncombustible concrete, or other noncombustible materialmaterial
Must have noncombustible fire Must have noncombustible fire doors and shuttersdoors and shutters
13e
Design and construction of Design and construction of spray roomsspray rooms
Adequate ventilationAdequate ventilation• the atmosphere in the breathing zone the atmosphere in the breathing zone
of the operator must be maintained in of the operator must be maintained in accordance with the requirements of accordance with the requirements of 29 CFR 1910.94(c)(6)(ii)29 CFR 1910.94(c)(6)(ii)
13f
Design and construction of Design and construction of spray roomsspray rooms
Spray rooms used for production Spray rooms used for production spray-finishing operations must spray-finishing operations must conform to the requirements for conform to the requirements for spray boothsspray booths
13g
Ventilation during spray Ventilation during spray finishing operationsfinishing operations
Ventilation must be provided in Ventilation must be provided in accordance with provisions of 29 accordance with provisions of 29 CFR 1910.107(d)CFR 1910.107(d)
14a
Ventilation during spray Ventilation during spray finishing operationsfinishing operations
Where a fan plenum is used it Where a fan plenum is used it must be of sufficient strength or must be of sufficient strength or rigidity to withstand the differential rigidity to withstand the differential air pressure or other superficially air pressure or other superficially imposed loads for which the imposed loads for which the equipment is designed and also to equipment is designed and also to facilitate cleaning - 29 CFR facilitate cleaning - 29 CFR 1910.94(c)(5)(iii)1910.94(c)(5)(iii)
14b
Ventilation during spray Ventilation during spray finishing operationsfinishing operations
Inlet ductworkInlet ductwork
Exhaust ductworkExhaust ductwork
14c
Velocity and air flow Velocity and air flow requirementsrequirements
Except where a spray booth has an Except where a spray booth has an adequate air replacement system, adequate air replacement system, the velocity of air into all openings the velocity of air into all openings of a spray booth must be not less of a spray booth must be not less than that specified in Table G-10 of than that specified in Table G-10 of 29 CFR 1910.94(c) for the 29 CFR 1910.94(c) for the operating conditions specifiedoperating conditions specified
15a
Velocity and air flow Velocity and air flow requirementsrequirements
Adequate air replacement systemAdequate air replacement system
Total air volumeTotal air volume
15b
Velocity and air flow Velocity and air flow requirementsrequirements
Respirator is required when the Respirator is required when the operator is downstream from the operator is downstream from the object being sprayedobject being sprayed
Downdraft booth doors must be Downdraft booth doors must be closed when spray paintingclosed when spray painting
15c
Make-up air in spray Make-up air in spray finishing operationsfinishing operations
Clean fresh air must be supplied to Clean fresh air must be supplied to a spray booth or room in quantities a spray booth or room in quantities equal to the volume of air equal to the volume of air exhausted through the spray boothexhausted through the spray booth
16a
Make-up air in spray Make-up air in spray finishing operationsfinishing operations
Self-closing doors, dampers, or Self-closing doors, dampers, or louverslouvers
Filtered air supplyFiltered air supply
Heating make-up airHeating make-up air
16b