Revision Cards Unit C

7/30/2019 Revision Cards Unit C

1/58

Tips to help with this exam

Read the question! pick out the key words

Try to relate the question to a workplace

situation

Break questions down e.g.. design, use,

maintenance where appropriate

Remember HS principles e.g.. RA,Controls, People


2/58

Electricity at work

regs 1989

Regs 1 -3

1 Citation

2 Interpretation

3 persons with duties

Reg 4 Systems, work activities & protectiveequipment

Systems must be maintained to prevent danger

All work activities must be carried out in a

manner not to give rise to danger

Equipment provided to protect people working

on live equipment must be suitable and

maintained

Reg 5 Strength & capability of electricalequipment

Must be able to withstand effects of its

load

Must be able to withstand effects of

transient or pulse currents

Reg 6 Adverse or hazardousenvironments

Must be suitable for the environment and

conditions that are reasonable foreseeable

Mechanical dame e.g.. vehicle, people

Weather, temp, pressure, natural hazards

e.g.. bird droppings

Wet, dusty, corrosive conditions, presence

of flammable dusts

Flammable or explosive atmospheres

Reg 7 Insulation protection & placing ofconductors

Prevent danger from direct contact

through insulation etc

Reg 8 Earthing or other suitableprecautions

Purpose to prevent harm from indirect

contact e.g.. casings

Reg 9 Integrity of referenced conductors

Ensure electrical continuity is never broken

Reg 10 Connections must haveadequate mechanical strength e.g..

plugs

Reg 11 means of protecting from excesscurrent e.g.. fuse, RCD

Reg 13 Precautions for work on equipmentmade dead

Identify the circuit, dont assume the labelling

is correct

Disconnection & isolation e.g.. isolation

switches (lock off) removal of fuse/plug

Notices, signage and barriers

Prove system dead test the test device

Earthing

PTW

Reg 12 Means of isolation

Reg 14 Work on or near live conductors

Competent staff

Adequate information

Suitable tools: insulated tools, protective

clothing

Barriers or screens

Instruments and test probe to identify what

is live and what is dead

Accompaniment

Designated test areas

PTW

Reg 15 Working space, access & lighting

Where there are dangerous live exposed

conductors space should be adequate to

Allow persons to pull back from the hazard

Allow persons to pass each other

Lighting should be adequate preference e to

natural then artificial

Reg 16 Persons to be competent toprevent danger and injury

An understanding of the concepts of

electricity and the risks involved in workassociated with it

Knowledge of electrical work and

qualification in electrical principles

Experience

Knowledge of systems of work & ability to

recognise risk & hazards

Physical attributes to recognise elements

of the system e.g.. not colour blind


3/58

Robot Safety

Groups at risk

Operators

Maintenance

engineers

Teachers

Interlocked perimeter fencing

Positioned to prevent access to

dangerous parts

Normally 2 meters high

Rigid panels

Securely fastened to floor

Infill suitable to protect from other hazards

e.g.. ejected materials

Gates/access points to be interlocked

Hinged/sliding interlocks

Trapped key exchange

Solenoid lock

Emergency Stops provided at

Control stations

Teacher control pedestal

All workstations

Other positions as necessary

Layout (Envelope)

Planning during design

Minimise need to approach robot

Good viewing arrangements outside

of enclosure

Adequate distance between robot &

enclosure

Prevent trap points

Adequate access to rescue injured

person

Access only throughinterlockedgates or similar

Electro-sensitive safety systems

Used in conjunction with fencing

Photo cell device

Trip with use of light curtains

arranged

vertically/horizontally/diagonally

Pressure mats around machinery

Trip wires etc robot comes into contact

with a person should trip

All should require manual restart

Positive stops

Limits movement of robot

Defined limits to prevent trap points

Avoid creating additional trap points

Brakes

Prevent danger of fall under gravity

Should be applied automatically when

machine stops

Entry Procedures

SSOW defined/RA carried out

Analysis of hazards in all possible

modes of operation

Release of stored energy before

entry/work

PTW ISOLATION required

Preventative maintenance and

inspectionsSoftware checks to avoid aberrant

behaviours

Stop devices

Guard checks

Integrity of parts for wear damage

e.g.. hydraulic rams

TEACHING

Remotely where possible

Slow mode when live

Behavioural - People

Hazard aware

Trained in procedures e.g.. entry,

emergency

Adequately supervised


4/58

Machinery Essential health

and safety requirements

that should be addressed

Reference Supply of machineryregs 1992 schedule 3

Consider

Installation

Use

Maintenance

Decommissioning

General

Principles of safety integrations

Materials & products used/created

Lighting arrangements

Handling & Installation of machine

Controls

Safety & Reliability

Control devices

Means of starting stopping device

Normal stopping

Emergency stopping

Mode of operation selection

Failure of power supply

Software design

Failure of control circuit

Indicators

Information devices

Warning devices e.g.. alarms/lights

Warning of residual risks

Markings

Instructions

Protection against other hazards

Electricity e.g.. insulation Other stored energy e.g.. hydraulic

pressure

Errors of fitting

Fire/explosion

Noise

Dust/gases e.g.. extraction

Vibration

Radiation

Required Characteristics of guards

Fixed

Movable guards

Adjustable guards

Special requirements for protective

devices

Protection against mechanicalhazards

Stability/anchorage e.g.. floor fixings

Risk of break up during operationFalling objects/ejected parts

Surface risk e.g.. sharp/hot/cold

Variable speeds

Moving parts

Choice of protection arrangements

Maintenance

Machinery maintenance

Access to operating and servicing

position

Isolation of energy sources

Operator intervention

Cleaning of internal parts

Lubrication etc


5/58

Range of issues &

evidence to examine

during investigation of lift

op failure (crane)

Key Factors

Crane

Lift

Forensic evidence

Lift

Load

Weight

Gravity lifting point?

Slinging method appropriate for load?

Type of lift Static

Slewing

Lift & Travel

Drag

Site conditions e.g.. wet, windy, foggy,

obstructions/excavations

Lifting plan, witness statements visual

inspections

Training records

Crane driver, slingers, rigger, banksman

Forensic evidence

Type of failure

Buckling

Brittle

Ductile

Integrity of Jib look for evidence of

alterations, repair, corrosion, missing

bolts

Settings & functionality of controls,switches & alarms

Crane

Typesuitable for lift?

SWL of crane

Alarm system working?

SWL indicator/radius indicator

Exceeded?

Operational criteria e.g.. adequate

strength & stability

Design characteristics

Counter balance

Out riggers

Configuration for task e.g.. level

ground, positioning to load, distance

required to travel

Maintenance & certification records

Lifting history


6/58

Factors Effecting

Structural Safety

Subsidence

Signs of defects include

Semi random cracks in walls

Sagging in arches/beams

Fractures of pipe joints

Builds over mine tunnels or large

holes can cause serious deformation

Dead loads

Material which buildings is

constructed from e.g.. columns,

beams, floors

Wind

Physical damage

Dampness by driving rain moisture

into buildings

Can lift roof covering

Vibration & Sudden Shocks

Traffic/machinery

Can effect foundations of buildings

Buildings can be struck by

vehicles/plant

Solar Radiation

Absorbed when it strikes a material

Materials expand when warm

Contract when cooling

Solar radiation causes surfaces to

heat up quickly

Rain falling onto hot surfaces can

causes severe shock and result in

tension cracking e.g.. roof membrane

Live Loads

People

Furniture

Equipment

Constantly moving and changing every

day

Dynamic loads

Dead loads & Live loads changeslowly and are called static loads

Other loads can change suddenly such

as wind gust, these loads are dynamic

Rain/snow/hail

Moisture greatest cause ofdeterioration

Rising damp causes flaking and

cracking

Frozen water causes stresses &

cracks

Moisture promotes rust in metals

Moisture creates environment for

fungal growth

Build of snow/ice on roofs increasesstructural loading

Atmospheric contaminants

Combine with moisture to form acid

rains which attack materials

Sulphur dioxide

Carbon dioxide

Oxygen Ozone

Timber Decay

Deterioration of timbers can

severely cases lead to building

collapse

Due to wet rot/dry rot/fungal attack

& insect attack

Corrosion

Metal combines with oxygen in theair to form rust

Key Factors

Dead load

Live load

Dynamic load

Solar radiation

Vibration/sudden shocks

Weather

Atmospheric contaminants

Timber decay

Corrosion

Subsidence


7/58

Effects Fire on

materials

Steel

Will expand with heat

Loss of strength normally @600

Celsius

Deform & Buckle

When cooled will regain strength but

properties may have changed

Acts as conductor transferring heat

thus spreading fire

Concrete

Limited expansion

Cracks and spalls made worse by

expanding reinforcement steel e.g..

rebar

Poor conductor of heat

Will have lost structural strength

when cool

Wood

Thin sections will burn promoting fire

spread

The charred surface of thick timber

will act as insulation to inner timber

Dependant on species

Generates smoke & allows surface

propagation of fire

Strength after burning depends on

original thickness and proportion loss

to fire

Precautions to prevent

failure of materials

Steel

Concrete cladding

Compartmentalise to reduce

conduction

Automatic cooling with sprinkler

system etc.

Concrete

Selection of type and mix to

improve fire resistance

Increase thickness of concrete

from exposed surface to steel

reinforcement (rebar)

Wood

Selection of thick timbers

Selection of timber e.g.. hardwood

burns slower than soft wood

Treat with fire retardant substance

General precautions

Sprinkle system

Fire resistance cladding

Early fire detection

Control of ignition sources & reduction of fuel type materials fire riskassessment and adequate controls implemented


8/58

Confined space

entry

Key Factors/Regs

Confined space regs

Reg 4(1) Avoid

Reg 4(2) If must SSOW to be

defined

Reg 5 Define Emergency

rescue plan

Specified occurrence

Fire or explosion

Loss of consciousness/asphyxiationfrom gas, fumes or lack of oxygen

Drowning

Asphyxiation arising from free

flowing solid e.g.. mud slide

Loss of consciousness arising from

high temperature

Reg 5 Emergency planning/Procedure

Communication with workers in

vessel/space

Raising the alarm

Emergency rescue e.g.. tripod winch

Provision of stand by man/first aider

Means of fire fighting

Provision of emergency escape sets

Communication with emergency services

Reg 4(2) SSOW

Risk assessment to consider

People conducting work e.g.. age,

experience, training

Likelihood of flammable/explosive

atmosphere from previous contents

Access/egress

Contaminated air from previous contents

Build up of heat

Duration of activity

Lack of oxygen

Working at height within CFP

Ingress of solids/liquids

Impact of other plant

Outside environment Weather, other

activities

Isolations required

Emergency situation

Reg 4(2) SSOW cont.

Control measures

Trained and experienced workers to conduct activity

Entry procedures, use of equipment e.g.. BA

Purge of space with inert gas e.g.. nitrogen

Forced air ventilation

Atmospheric testing e.g.. gas/oxygen level monitoring

Suitable electrical equipment e.g.. intrinsically safe

Earthing arrangements

Job rotation e.g.. control of heat fatigue

Appropriate access and egress e.g.. scaffold, ladders

WAH provision, e.g.. scaffold internal of space

Barriers to prevent unauthorised access

Appropriate isolations as necessary

Appropriate PPE e.g.. anti static clothing, BA, gloves etc.

Reg 4(1) Avoid if possible

Consider other options

Cameras

Cleaning lances

Robotic inspection

Last paper


9/58

Key factors to protect

against ignition from staticof a flammable vapour

during transfer of

containment of liquids

Worker involved trained and

competent in operation e.g..

aware of hazards and

precautions necessary

Over fill protection system

e.g.. high level indicator,

interlocked shut down

Avoid splash/spray filling

Controlling pump rate

Speed slow not to

propagate static build up

Use of inert gas blanketing

above the liquid

Earthing of all conductive

surfaces e.g.. tankers, pipe

work, containers e.g.. IBCsKeep at zero potential,

Earthing should be

interlocked to pump system

Provision of anti staticclothing including footwear

Implementation of a vapour

return system

Complete containment of

flammable liquid, not leaks,

seals joints etc

Last paper


10/58

EPA section 34

Concepts of duty of

care

Controlled waste

Household

Commercial

Industrial

Exceptions

Agricultural

Mines/Quarries

Radioactive waste

Key points

Controlled waste

Duty of care categories of

persons

Duty of care

Duty of care

Reasonable steps to prevent;-

Deposits of CW without waste management license

Treatment, storage, disposal in manner likely to cause

pollution

Treatment, storage disposal with out waste handling license

Prevent escape

Transfer to unlicensed holding

Transfer without written description

Duty of care Categories of persons

Persons who

Produces CW

Imports CW

Carries CW

Stores CW

Treats CW

Disposes of CW

Exceptions of house holders


11/58

Automatic Fire DetectionHeat Detectors Fixed temperature type

Thermocouple detects when a settemperature is reach

Rate of rise type Detects abnormal temp rises

(sudden)

Electronic resistors Usually incorporate fixed temp

element as well

Unsuitable for Rapid heat rise workplace e.g..

laundrettes, steel manufactures

Smoke Detectors Ionisation type

Small radioactive source to ionise achamber into which smoke entersduring a fire. Detector reacts tochange in current caused byneutralisation of ions by smokeparticles

Optical typeResponds to the obstruction of a

focused light ray or the scattering oflight from an optical ray by smoke

Unsuitable for Dusty workplace due to false alarms

e.g.. flour mills

Workplace which generate smoke e.g..kitchen, welding workshops

Heat (fixed or rate of rise) where there are fumes, steam or other particles may be present that would be

detectable by a smoke detector and cause false alarms.

Smoke (optical or ionization) everywhere else within reasonLast paper


12/58

Issues to address

when planning a fire

evacuation

Publishing and training ofprocedure

Regular drills

Documented

Fire log book

Numbers of people to evacuate& physical ability

Escape routes

Distance of travel required

Alternatives routes

Equipment and security

Equipment may need shuttingdown safely

Security could be an issueafter evacuation

Emergency light and signs

Exits

Escape routes

Refuges and safe havens(muster points)

Raising the alarm

Consider any disabilities andmake provision for e.g.. visualalarm for deaf people

Contacting the emergency

service e.g.. interlocked alarmsystem or manual call

Training of fire wardens

Zoning

Areas of responsibilityRoles and responsibilities

Managers

Staff

Prevention of re-entry

Liaison with emergency services

Numbers of people involved Specific hazards in building

Accounting for people


13/58

Reducing risk of dust cloud

explosion and mitigating

explosion effects

Key principles

Dust control

Ignition source control

Mitigation of explosion effects

DSEAR regs

Zoning

Ignition control

No smoking policy

No mobile phones

Provision and use of anti

static clothing and footwear

Earth bonding of equipment

Assessment in compliance

with DSEAR regs

Appropriate zone identification

of areas i.e.. 20, 21 or 22

Use of spark protected

equipment intrinsically safe

to appropriate zone

Abnormal activities generating

sparks under hot work PTE

Dust control

Damping down

Extraction of dust at point of transfer

(LEV)

Interlock device to prevent

overfilling of vessels

High standard of house keeping

Ensuring that systems are sealed

where possible

Mitigatingeffects of explosion

Equipment able to withstand

explosion

Venting and explosion panels

Bursting disc on vessels

Suppression inerting

Compartmentalisation minimise

effected


14/58

Design features toreduce risk of

vehicle/pedestrian

collision

Where possible re-route

pedestrians away from

vehicle movement area e.g..

elevated corridors

Allow sufficient space for

vehicles to operate

Introduce safe crossing

points e.g.. zebra crossing

Segregate pedestrians from

vehicles with the use of fixed

barriers

Avoid creation of blind bends

if unavoidable install wallmounts mirror (convex) to

improve visibility

Create safe passing places

Separate access & egress points

for vehicles/pedestrians

Direction of vehicle

movement control e.g.. force

one way traffic

Where possible design

routes such to

eliminate/reduce the need for

reversing

Ensure lighting is adequate

and suitable for tasks carried

out

Consider automated system

(robotic to almost eliminate

pedestrians requiring access


15/58

Aspects of a working

environment whichincrease electrical risk

Mechanical hazards

Vehicle impact

Plant equipment nearby

Abrasion from operate

equipment

Corrosive atmospheres

leading to corrosion of parts

Weather conditions

Rain moisture entering

Freezing leading to crack

through expansion

Heat

Humidity

Flame proof

Heavy duty of substantial build and enclosed. When

flammable atmosphere enters the equipment can withstand

and enclose an explosion and prevent the ignition of any

flammable atmospheres surrounding equipment

May not be suitable for use in areas with combustible

powders of dust. May require special measure to preventingress of water

Flammable/explosive

atmosphere

Intrinsically safe

Restriction of electrical energy in

equipment, insufficient to create

heat/sparks

Faults may increase energy levels above

safe limit

High/Low temperatures


16/58

Duties of designers

under CDM2007

Duties apply at all times e.g..

appointing of CDM co-

ordinator if notifiableEnsure that client is aware of

their duties

Ensure that they (designers)

are competent for the work

they do

Co-operate with others as is

necessary to manage risks

e.g.. contractors

Provide information for h & S

file

Take into account Workplace

(HS&W) regs when

designing workplace

structures

Co-operate with CDM co-ordinator &

other

Conduct risk analysis of

major design e.g..

HAZOP/FMEA

Inform of any

significant/unusual residual

risks

Avoid foreseeable risks(construction and use)

SFAIRP during design by

Eliminating hazards where

poss.

Reduce remaining risk

Give collective risk

reduction measures priorityover individual measures

Provide info with the design

to assist clients, contractors,

designers e.g.. notes for

drawings, rational behind

design decisions


17/58

Safe operation of bench

mounted circular saw

Safe operation and

adjustment of top guard

Provision of emergency

stops and means of isolation

Use of appropriate PPE e.g..

hearing protection/goggle,

dust mask

Effective guarding of blade

under bench

Use of push stick to feed

materials being cut

Ensure that operators are

suitable trained and

experience to use the saw,

also ensure appropriate level

of supervision

Ensure that the riving knife is

correctly positions through

risk assessment

Sufficient space around

equipment kept clear of

obstructions

Provision of LEV to remove

dust

Adequate lighting and saw

suitably fixed to floor

Regular maintenance andsafety inspection e.g.. guard

check


18/58

Pressure systems

causes of failure

ExcessiveStress

Ductility amount of stretch before amaterial ruptures

Usually result of single stress over

load

Materials can balloon due to

excessive pressure

Abnormal external loading

Struck by something e.g.. vehicle

FLT/Fuel tankers Explosion

Over pressure

Catastrophic results e.g.. vessel

rupture

Failure of relief valves can cause

Normally systems tested to 3 timesnormal operating pressure

Brittle fracture

Fracture without deformation

Brittle materials are strong but not

resistant to cracks

Impact loading causes e.g.. rapid

temp changes, pressure differences

High tensile & residual stresses

promote

Thermal fatigue & Shock

Shock is sudden change in temp of

water

Causes rapid expansion/contraction

of system components

Leads to fatigue and material stress

ultimately failure of system e.g..

leaking pipes, fracture of vessels

Mechanical fatigue & Shock

Pressure causes tensile stress in all

directions

If stresses are greater than material

can cope with it will lead to ductile or

brittle failure

Fatigue stress is usually progressive

Fatigue failure often triggered by

surface interruption e.g.. grinding

marks, weld defects, notches etc Pressure focuses at root of defect

Overheating

Can occur if alarms/controls fail

Causes rise in pressure

Creep

Under constant load

Deforms over time (plastic)

Temperature is important, materials

determine working temperatures that

can be used

Hydrogen attack

Hydrogen seeps into gaps in

molecular frame work

Causes stresses within framework

Examples are cathode reaction,electroplating

Corrosive Failure

Chemical/electro-chemical attack by

atmosphere

Only affects metals

Materials lose strength can thin

Occurs when oxygen levels of

carbon dioxide levels are high &

when PH levels are low or high


19/58

Technical & proceduralmeasures to minimise

likelihood of pressure

system failure

Key points

Design

Operation

Inspection/Maintenance

Inspection

Written scheme of examination

statutory

Pressure vessels

Pipe work and valves

Protective devices

Pumps and compressors

Prepared by competent person

NDT/examination

Operation

Use within performance envelope

Operators trained and experience to

identify errors and prevent faults

through error arising

Aware of safe operating limits

Scheme of examination Equipment marked with operating

pressures/temperatures max/min

Quality control

Filtering/treating of water (boilers)

Design

Take account of current safe practise

Fit for purpose/CE marked

Material constructed from suitable for

materials in process

Expected life

Maintenance/testing accesses

Operating pressures and provision of

safety devices e.g..

Safety valve (PRV)

Gauges

Level Controls

Blow down valves

Pressure gauges


20/58

LPG in cylindersprecautions

(storage)

Control of ignition sources

No smoking

Storage of cylinders away frompotential ignition sources e.g..fabrication shop

Control of mobile phones

Storage area regarded as zone 2so only zone 2 IS rated electrical

equipment to be used

Signage stating highly flammable

Dry powder fire extinguisherlocated close to storage area

Concrete level floor, surroundingarea kept free of vegetation (notwith use of oxidising week killere.g.. sodium chlorate

Stored away from excavations,drains, pond, rivers, cellars at least3 m

Cylinders stored in upright position

Stored away from any oxygen

cylinders. oxidising substances

Empty cylinders stored separatelyfrom full cylinders, caps fitted tovalves. Well ventilated

Protected from elements werepossible

If more than 400Kg stored musthave 2m high mesh fence andcylinders at least 1.5m away fromfence with 2 exits

Any store room must be non-combustible or fire resistant andventilated with and explosimeterinstalled

Properties of LPG

Flammable at standard temp &pressure

Denser than air

Liquid form floats on water

LEL is reached in smallconcentrations

Can cause suffocation in high

concentrations

Storage compound designed toprevent vehicle impact


21/58

FLT safety

Causes of instability Lateral (sideinstability)

Insecure load

Drive laterally on slope (angle ofslope, elevation of load

Hitting obstruction e.g.. curb

Uneven ground

Cornering (fast, sharp)

Poor tyre condition/unevenpressures

Key points

Instability

Training

Refresher training circumstances

Causes on instability Longitudinally(Front to back instability)

Overloaded vehicle

Incorrect positioning of load onforks

Load slipping forward(inappropriate tilt of mast

Driving with load elevated

Changing tilt

Driving forwards down slops

Driving backwards up slopes Sudden braking

Striking overhead obstruction

Training

Basic training (CITB/RTITB)

Operating truck

Maintenance & checks

Specific job training

Specific truck type operation

Use of truck in various conditions

Work to be undertaken & SSOW

Familiarisation training under supervision

Site layout

Types of storage/load e.g.. racking

Local emergency procedures

Refresher training appropriate

Operator not used truck for some

time

Been involved in accident/nearmiss

Developed unsafe practices

Change in working practice

Best practice every 3 years or asper company policy


22/58

Methods and devicesdesigned to improve electrical

safety + precautions to be

taken when maintaining or

repairing systems

Fuse

Protects systems not people normally

Prevents overloads of electrical systemand overheating of electrical wiring

Limits shock under severe faultcondition

Limits over currents Does this by the heating effect of electric

current which melts the metal link ifcurrent exceeds the design value

Remains broken until replace

Miniature circuit breaker

Close tolerances for designcurrent flow and speed ofoperation

Provide visual detection followingoperation (e.g.. switch to offposition

Need to be reset after faultdetection

Are reliable

Design to protect system

Reduced voltage system e.g.. 110V

Transformer

Supply centre tap to earth consist of

Earthed systems

Class 1 equipment

Double insulated class 2 equipment

Required procedural measures to be followed

Precaution to be taken when maintainingor repairing electrical systems

Identify equipment to be worked on

Obtain system drawings & information

Consider whether work can be donedead SSOW for dead:

Isolation/lock off

PTW

Proved dead

Test test equipment

If work required is live SSOW:

Screening of conductors nearwork

Testing live conductors throughholes with probes

Use of suitable test equipment

Have testing arrangements inplace for testing equipment

Consideration of accompaniment

Consideration of insulated tools

Adequate space

Adequate lighting

Residual current devices or earth leakagecircuit breakers

Shock limiting device not system

protection

Shock is still received but time reduced

Monitors balance of current in line andneutral

Operates on earth leakage fault

Live and neutral disconnect from localpower supply

Key points

Fuses

Miniature circuit breakers

Residual current devices

Reduced low voltage systems

Precautions to be taken


23/58

Safety provisions required for

receiving and storing acids andalkalis

Operation

SSOW

Operation of equipment

Emergency procedures e.g..spill response

Training

Tanker drivers

Operators

Provision of PPE e.g.. chemicallyresistant suits, gloves, full face visor

Maintenance

Arrangements for examination andinspections

PTW system

Isolation procedures

Cleaning prior to work e.g.. purge

Regular cleaning of bunds

Provision of training to maintenancestaff both maintenance andemergency

Design

Material to be used for vessels andpipework

Suitable to withstand corrosivenature of substances

Layout of facility

Segregation between acid/alkalise.g.. compartmentalisation

Design and position of inlets

Prevent cross connection

Bunding of tanks

Separate bunds

Capacity 110% of largest containermin

Bunded sealed with appropriatematerial (with stand corrosive)

Safety devices

High level indicators

Isolations

PLC control

Interlocked system

Adequate lighting

Adequate access and egress

Arrangements for spill containment

Labelling of system e.g.. flow direction ofpipes

Emergency arrangements e.g.. drenchwater safety shower


24/58

Runaway reactions

Temperature Increase speeds upreaction Le Chateliers principle

If the heat released from reaction isnot controlled/removed reaction willspeed up exponentially

Can result in

auto ignition explosion

Catastrophic over pressureresulting in loss of containmente.g.. vessel rupture and toxicrelease

Violent boiling

Secondary competing reaction

Operational features to prevent

High calibre of operator experiencedand appropriate level of qualification

to operate process

Ensure that maintenance

activities/raw material handling dont

introduce potential catalysis into

reaction

Design features to prevent

Conduct HAZOP study

Appropriate temperature control system

e.g.. matrix cooler

High integrity temperature detection linked

to cooling/reaction addition protection

Pressure rise detection linked to

cooling/venting/auto shut down

Vessel protected by correctly sized bursting

disc linked to safe haven e.g.. secondary

vessel to dump reaction to

PRVs, weighted lids to realise pressure

Agitation of liquids to promote even tempdistribution

Causes

Failure of temp control (reactioncooling)

Strong exothermic reaction

Presence of containment catalysis

(speeds up reaction)

Chemical changes involve heat

Exothermic - Evolutes

Endothermic - Absorbs


25/58

BLEVE

Cylinder/container containingflammable gas under pressure e.g..butane pressure turns gas intoliquid state

Valve opened reduces pressureturning liquid into gaseous state

Cylinder exposed to heat sourcee.g.. caught in a fire liquids absorbsheat

Area unable to hold internal overpressure and ruptures

Area of cylinder just above liquidlevel starts to weaken/thin with heat

Liquid level falls heat continues

Liquids starts to vapour and isvented off

Sudden release of contentsresulting in

Blast wave (low)

Radiation (thermal) high

Missiles travelling long distances

Substantial thermal heat severburns e.g.. LPG cylinder BLEVE hasserve burn range of 35m

Examples of incidents

San Carlos

Crashed over loaded road tanker

Explosion

216 Dead

Mexico city


26/58

Reducing cost and

environmental impact

of hazardous waste

(sludge)

Identify recycling opportunities atall stages of process

Substitute process materials for

ones that give rise to nonhazardous waste

Improve production efficiency toproduce less waste

Exchange waste streams to other

companies which could use wasteas raw material e.g.. waste solventsto paint producers

Selection of waste contractors thatcan process the waste

Treat waste to reduce hazardousproperties e.g.. ph balancing

Treat waste on-site to reducequantity (De-watering)

Explore other disposal means(incineration, liquefied waste tosewer)

Explore becoming licensed to savecost e.g.. EA permit

Last paper

P rpose


27/58

NDT

Dye testing

Put dye on

Dye penetrates making cracks visible

Cheap & simple (pro)

Doesnt detect sub surface faults

(con)

Not totally reliable (con)

Can be enhanced by usingfluorescent penetrate and UV source

Penetrate may be toxic (con)

Need good eyesight

Impact (tap testing)

Strike surface

Changes in pitch of reverberantsound

Cheap (pro)

No indication of where fault is

located (con)

Relies on individual skill (con)

Radiography

X-rays/Gamma rays penetrate item andleave an image on film

Defects are shown up by differences in theintensity of the radiation striking the film

Detects internal defects and a permanentrecord is created

Expensive

Bulky equipment

Present radiation hazard and tight controls

are required Skilled radiographers are needed

Eddy current testing

Surface and near surface crack detection

Electromagnetic method/instrumentation

Can be used to verify materials heat treatcondition

Can be automated (pro)

Can suffer from spurious defectindications

Doesnt work on non-conductive materials

Relatively expensive and requires skilledoperator

Magnetic particle

Coat surface with magnetic poweror liquid

Simple & Quick

Very sensitive to surface cracks

Interpretation of results can bedifficult particularly on inside ofvessel

Ultrasonic Technique

Short pulses of high frequencyultrasound are used

Reflected waves detected and shownon digital display or oscilloscope

Surface and sub-surface defects

Only requires one side of joint

Quick to perform

Suitable for most environments

High level of expertise required

Coupling equipment onto roughsurfaces can be difficult

Other techniques

Pneumatic testing

Hydro testing

Purpose

Check for faults (e.g.. cracks) incomponents before they developinto total failure without affectingintegrity of the component


28/58


29/58

Safety aspects to considerbefore starting external

maintenance/constructionworks on build with public

facing front (footpath) workincludes roof

Access & Egress

Maintenance workers

Pedestrians

Building workers

Vehicles

Public safety

Falling objects

Screening

Segregations/barriers

Security

Fencing

Dust damping

Noise levels

Welfare facilities

Washing

Toilets

Rest/eating etc

Plant and equipment requirements

Suitability

Availability

Building workers safety

Safe systems of work

Provision of PPE

Fall protection

Scaffolding

Edge protection

Signage

Hazardous materials present e.g.asbestos

Emergency arrangements

Alarm

Muster points

Escape routes

Storage of materials

Hazardous

Flammable

Housekeeping

Lay down areas

Traffic management

Deliveries

Plant

MEWPS etc


30/58

Factors that could

contribute to a delay in

evacuation + benefits

of regular drills

Fire Alarm Design/maintenance

Quiet

Does not extend into all partsof building

Poorly maintained sounders

Faults within infrastructureleading to partial failure insome areas

Deficiencies in procedure

Difficult to understand

Poorly communicated

Not exercised

Poorly planned escape routes

Untrained staff

Execution of procedure

Delayed response to alarm

Staff not reacting quickly

Finishing of phone calls

Switching off equipment

Fire Marshalls not followingprocedure

Blocked escape routes

Staff not trained

Poor response perhaps many

false alarms have occurred in past

Human factors

Hearing disabilities

Belief that false alarm

Belief that above evacuating

Waiting for direct notificatione.g.. phone call

Routine violations

Benefits of regular drills

Compliance with legalrequirements FFRO

Efficient evacuation in future

Highlights deficiencies in alarm,procedure and evacuation

Allow practise of scenarios suchas abnormal normal route use etc

Refresh staff training andawareness of procedure


31/58

Introduction of Automated Guided Vehicle to

Warehouse

Risks Reduced

Manual handling

Pedestrian/vehicle collision

Racking Collisions

Falling objects less likely tocontact person

WAH access to racking

Reduction of noise

FLT collisions

Incorrect order picking

Risks Increased

Programming dangers (teachers)

Interference in signal

Proximity sensors to prevent

pedestrian contact

AGV collision

Guarding of order picking

machinery

Dropped loads to be dealt with in

automated area

Maintenance activities forequipment

Software failure


32/58

Precautions to be

taken before &

during repair workof a 15m high grain

silo on farm (with

welding required)

Planning & Organising

Consider work to be carried outand devise RA & MS

Nominate supervisor for task

All workers briefed on general &specific risks

Suitable equipment for task e.g..PPE, tools, access etc

Preparation of Silo

Emptied

Locked off to prevent fillingmovement of parts

Residue removed before hotworks

Damped down

Signage erected of work inprogress etc

Working area

Excluding non essential personnel

Erecting barriers

Sighting of warning signs

Working at height

Use of platforms

Handrails

Toe boards

Harnesses if required

Protection of fragile sections ofsilo top

Confined space entry

PTW control

Ventilation

Trained staff

Emergency rescue plan definedand trained

Ensure suitable access andegress

Oxygen monitoring


33/58

MEWPS

Hazards

Falls from height of persons/materials

Instability of vehicle e.g.. unevenground

Being struck by other vehicles

Trapping & impact hazards Mechanical failure

Contact with over head power lines

Exposure of workers to adverseweather conditions

Requirements for safe use

Selection of trained competent operators

Persons may be connected to MEWP withfall restraint

Toe boards installed/use of tool wrist straps

Barriers installed to protect area MEWP

used in Correct positioning e.g.. level firm ground,

not close to over head services, use ofoutriggers where installed

Prevent of use in adverse weatherconditions

Not exceeding SWL

Regular inspections & maintenance Ensure trap points are guarded

Ensure used in locked position

Prohibit transfer of people/materials whilst inraised position


34/58

To supply machine

under SMSR1992

process

Satisfy Essential health and safetyrequirements and be safe

Safe and reliable control devicesincluding normal operation andemergency controls

Stable

Protection against mechanical

hazards e.g.. moving parts guardedProtection from other hazards e.g..vibration, electricity & noise

Maintenance activities

Adequate indicators e.g.. alarmsand warning light etc

Preparation of technical file

Detailed drawings

Calculations, test reports

Description of methods used to eliminatehazards

Machinery RA

Instruction draw up in accordance withprovision of information

Satisfy requirements of

EHSR

Responsible person to

prepare technical file

Responsible person to

ensure machine meets

requirements of other

EC directives

Issue a Declaration of

conformance

Fix the CE mark in a

visible, legible and

obvious manner Last paper


35/58

Factors to consider

when devising

scheme for PAT

testing

Inventory of all equipmentrequiring examination andtest to be made and uniquemeans of identificatione.g.. number system

Determine appropriatefrequency of inspection for eachitem based on factors affectinglevel of risk e.g..

Type of appliance

Protective systems used

Use

Frequency of movements

Earth boning

Age

Environment which applianceused in

Experience and competence ofuser

Historical information andmanufacturersrecommendations

Electricity at work regs and HSEpublished guidance

Criteria for each type ofexamination defined includingissues such as

Competence of the tester

Calibration and maintenance oftest equipment

Format of records to be kept

Results of tests andexaminations

Systems to identify and removefrom use equipment that isfound to be faulty


36/58

Sources of Ignition from diesel powered vehicles and possible protection to

minimise risk of explosion in flammable atmosphere

Sources

Flames/sparks from exhaust/inletsystems

Sparks from vehicle electricalsystem

Static build up from overspeeding/loading the engine

Hot parts e.g.. exhaust

Protection

Fit spark/flame arrestors preventingflashback to atmosphere if drawn intoinlet system plus prevent any sparksfrom escaping system

Engine and exhaust system design toensure surface temps are belowignition temp of atmosphere

Use of water jacket around hot parts

Electrical equipment on vehiclesuitable for zones 1 or 2 wherepossible

Speed limiters to prevent speed at

which static could build up Use of electrically conductive materials

for parts e.g.. tyres to reduce staticbuild up.


37/58

Key safety features

of building used tostore highly

flammables

Bunding to contain spills

Facility to collect & dispose ofspillages e.g.. spill kit

Building constructed of fireresistant materials

Adequate distance from otherbuildings

Impermeable floor

Mean of segregation of materials

e.g.. low walls/dividers, cabinets

Roof lightweight and/or blast panels

High and low level ventilation

Adequate access and egress e.g.. 2points of entry/exit including rampto facilitate drum handling

Security features such as locks,alarms, and signage

Emergency lighting/appropriate EXrated electrical equipment e.g.. zone2 rated lights

Sprinkler systems/fire extinguishers


38/58

Design factors to

consider whenproviding a sprinkler

system

Capacity of water required andadequacy of existing supply

Design of pump system e.g..diesel back up if electrical pumpinstalled

Means of activating system(fragile bulbs or detectoractivated

Presence of substances whichreact violently with water

Area to be covered

Spray pattern required

Linkage of system to alarms

Height of any storage rackingand distance from sprinklerheads, possible protection fromvehicle movements e.g.. FLTtines

Provision of fire stopping watercurtains to prevent fire spread,compartmentalisation

Provision of water run off

Provision required for testingand maintenance


39/58

Possible mechanisms of structural failure of

building during storm

Adverse weather conditions

exceeding designed wind loading

capacity of structure

Excess weight on roof caused by

rain water or snow

Weakening of steel structure by

corrosion through roof leaks

Inoperation of rainwater drains

Alterations to structural members

which have invalidated original

design calculations

Subsidence or nearby

tunnels/excavation leading to

foundation instability

Vibration caused by traffic etc

leading to structural fatigue

Inadequate design and/or

construction of structure


40/58

H & S issues to be

considered whenplanning demolition

of building

Notification of HSE under CDM 2007regs

If building partially collapsedalready devise method fordemolishing to avoid prematurecollapse of the remainder

Protection of nearbybuildings/business/properties

Selection of and Inspection,maintenance of plant andequipment to be used

Identification of buried and/oroverhead services e.g.. powercables, gas pipelines

Precautions to prevent people orobjects falling e.g.. scaffolds, edgeprotection

Protection of public e.g.. barriers,signs, security

Identification of competentdemolition contractors

PPE required for workers e.g.. hardhats, ear protections safety boots,protective clothing, eye protectionetc

Site traffic management if required

Welfare facilities provision e.g..toilets, wash and rest facility plusmaybe lay down area forcontaminated clothing

Control of noise

Identification of hazardousmaterials, control of dust and saferemoval of waste from site use oflicensed carrier etc


41/58

Factors that cause instability of mobile cranes and measures to be

taken to reduce likelihood of overturning during operation

Causes of instability

Incorrect selection of crane e.g.. SWL to low

for lift

Incorrect sling of load

Unstable ground incapable of bearing weight

of crane and load

Uneven/sloping ground

Obstructions being struck by crane of things

striking crane e.g.. other plant of site

Exceeding SWL of crane of lift tackle

Inoperation of crane e.g.. incompetent,

inexperienced operator, not using out

riggers

Poor lift control by AP/banksman. Unsuitable lifting plan

Mechanical failure

Adverse weather condition e.g.. wind

Lack of maintenance of crane e.g.. incorrect

tyre pressures, rope not inspected etc.

Measure taken to avoid

Conduct full assessment of lift required and

surrounding areas including establishing the

load bearing capacity of the ground that the

crane will operate on

Define and implement sufficient lifting plan

use of competent appointed person

Selection of appropriate crane for lift

Ensure that maintenance and testing of

crane is adequate

Appoint competent person to supervise lift

i.e.. appointed person, competent banksman

Engineering controls e.g.. ensure that

outriggers are used and fully extended

where appropriate, ensure that capacity

indicator and alarms are functional

Ensure that the motion and performance

limit device are in working condition

Behavioural controls such as competence

and training of driver, slinger and banksman

Last paper


42/58

Precautions to be

taken when workingnear an overhead

electrical supply

Explore possibility of re-routingcables or making dead

Consult with utilities supplier beforetaking any protective measures

Identification of safe workingdistance i.e. 9 m if wooden or steelpoles 15m if pylons plus length ofjib or boom if cranes/excavators areto be used

Safe systems of work to be definedand implemented

Height restrictions on plant

Use of goal posts and/or tunnels

Use of barriers, marking tape andbunting

Supervision and hazard awarenesstraining for workers e.g.. toolboxtalk on hazard associated with cableand what measure need to be taken

to avoid

Warning signs and protection forpublic if necessary


43/58

Precautions to ensure

safe provision & use ofelectricity on construction

site (feed taken from

overhead lines)

Planning and assessment fordevelopment of electrical supply bya competent person

Safe positioning of transformerse.g.. protection from plant/vehicleimpact, barriers to prevent workersaccessing area

Routing, marking and protection forcables

Development of safe systems ofwork

Arrangements for testing and

maintenance of portable equipment

Arrangements for inspection andmaintenance of the fixed supply toinclude earth bonding checks

Use of protective devices e.g..reduced low voltage systems (110),RCDs and double insulated

equipment

Use of competent persons forinstallation work of electrical supply

Fatigue failure


44/58

Component failure

g

Crack propagation from points of stress concentration(e.g.. groves, weak weld points), fluctuating stress finalfailure may be ductile or brittle

Factors contributing

Surface occlusions/damage

Choice of material

Residual stress imposed through manufacture

Corrosion, temperature Measures to take to prevent

Design spec appropriate

Quality assurance on manufacture

Assembled according to spec

Correct use avoid misuse e.g.. over ,loading

Maintenance/testing NDT

Buckling (Compressive force)

Buckling yield of one side ofstructural member under axialcompressive loading


Excessive/non uniform loading

Weakening due to removal ofcross members

Use of out of true members e.g..scaffold tube at incorrect anglei.e.. not 90 under load

Excessive temperature

Measures to be taken to prevent

Design/material selection

Avoid overload work within spec

Temp control

Maintenance/testing NDT

Ductile Failure (stretch)

Ductile failure in metals occur when the yield stress of thematerial has been exceeded by the material being placed intension (stretched). The metal moves from its elastic region

into its plastic region and loses its shape. There is a

reduction in cross sectional area at failure point. The failurewill appear as a cone / cup at 45 degrees to the load along

the grain boundaries


High temperature

Over loading

Design inappropriate


Temp control

Selection/design of materials

Maintenance/testing

Operate within spec limits of equipment

Creep

Gradual yielding of material under stress close to elasticlimit (undergoes plastic deformation


Continuous loading

High temp e.g.. hot pressurised pipes, turbineblades

Overloading

Design spec etc


Temp control

Selection/design of materials

Maintenance/testing

Operate within spec limits of equipment

Brittle failure

brittle fracture, no apparent plasticdeformation takes place before fracture

Factors which promote brittle fracture Low temperature Inherently brittle material (cast iron) Impact or snatch loading (does not givematerial time to react


45/58

Gamma

Radiography

Gamma radiography uses the transmission of gammarays from a sealed ionising radiation source (isotope)through a test object onto a film placed on the oppositeside. The film records the intensity of the radiationreceived and since cracks and flaws are hollow, agreater intensity of rays pass onto the film showing up

defects as darker regions

Advantages

Permanent record produced.

Can be used to test most materials

Internal defects can be identified

Coupling with the surface of the testpiece is not required

Disadvantages

Poses a radiation exposure hazard to operators requiringspecific SSOW to be implemented

Can be time consuming due to application to HSE each timetest is required

Equipment can be bulking and difficult to move

Specialist operators are required and staff to interpret results

Results may take a long time to receive

Can be an expensive process to run

S f ifi ll t t lik l t b i t d ith lti f l CHP


46/58

Sources of specific pollutants likely to be associated with a multi-fuel CHP

power stations using either coal, oil or gas for burning under normal operations

and foreseeable abnormal operations (located on river estuary taking deliveries

by ship, road & pipeline) plant also has water treatment plant

Normal operations Emissions to air

Carbon monoxide & oxides ofnitrogen from burning of fossilfuels

Sulphur dioxide/sulphur

compounds when coal or oil isburned

Other pollutants Soot & coal dust from

incomplete combustion

Solid waste from coal & oil ash

Acid & alkali effluents fromwater treatment process

Emissions from vehiclesdelivering fuel to site same forships

Abnormal operations Leaks

Oil storage tanks

Gas supply pipelines

Acid/Alkali storage tanks

Spillage of chemical from roadtank accident

Oil slicks from ships duringoffloading or major disastere.g.. sinking

Fire leading to fire water run offduring fire fighting

Design of basket


47/58

Factors to ensuresafe use of FLT

man basket

Design of basket

Constructed for taskintended

Not exceed the width of FLT

Toe boards/guard railsinstalled

SWL indicated on basket ineither weight or no. of peoplepossible to carry, notexceeding 50% of FLT SWL

Guards fitted to protectagainst moving parts of FLTe.g.. chain

Basket maintained and inspected atleast every 6 months

FLT to be parked on firm, levelground, brake applied, driver intruck

Competent FLT driver

Anchorage point in cage andharness fitted and connected topersons in basket

Barriers positioned around workarea preventing collision from othervehicles and protect others againstfalling objects from basket

Cage securely fixed to forks andtruck not moved during activity

Trained and competent operator inbasket, aware of hazards associatedwith use


48/58

A petrol storage tank in a bund containing three similar tanks is overfilled

resulting in a large spillage of petrol into the bund. The petrol vapour exploded

Design & construction measures toprevent such an incident

Adequate segregation betweenadjacent tanks

Separate bunds for each tank

Interlocked pumping system withhigh level alarms min double redundancy

of alarms Level detection

Vapour detection system fitted inbunds

Remote shut down system

Good earth bonding

Measures to mitigate the effects Fixed foam installations capable to

spray the surface of pool in thebunded areas

Installation of foam monitors capableof reaching top of tanks

Radiation walls between tanks/bunds

to prevent other tanks from beingheated

Adequate supply of fire water

Installation of remote pumps to emptyaffected tanks

Easy route of access for fire fighters

Provision of drainage interceptors to

minimise enviro affects of fire waterrun off

Regular draining and cleaning toremove rainwater from bunds

Provision of site based emergencyresponse team.


49/58

Fixed guards factors to

consider in design and

use to ensure people are

adequately protected

Design

Material of construction sufficientlyrobust to withstand workplacerigours and contain any ejectedmaterials

Should allow sight of process ifrequired

Method of fixing should requirespecial tool to removed e.g.. torque

bolts Ensure that any necessary

openings provide enough distancefrom hazards to prevent harm

Guards reverberation exacerbatingnoise problems

Use

Monitoring and supervision toensure guards are notremoved/tampered with

SSOW fir carrying outmaintenance operations withguards removed

Guard check procedure to ensureguard is kept in maintainedcondition

Provision of information andtraining for operators andmaintenance staff detailing thehazards associated with guarddefeats and other SSOW

Fixed guard

Defined in BSENISO12100 as a guard fixed insuch a manner (e.g.. by screws, nuts, welding)that can only be removed or opened by the useof tools or destruction of the affixing means. Itprovides protection against mechanical hazardswhen infrequent or no access is required during

normal operation of the machine. Acts as afence between people and dangerous machineryparts


50/58

Fixed electrical systems faults (including corrosive atmospheres) & Information

relating to system that electrician would need before conducting a survey of

system

Type of faults found in fixed electrical

system (including systems in area with

corrosive atmosphere

Poor earth bonding

Damaged sockets and switchgear

Covers missing from junction boxes

Incompetent workmanship and

inadequate excess current protection

Exposed conductors due to damaged insulation

from corrosive

Short circuits caused by ingress of fluidsCorrosion of system parts

Unsuitability for use in wet & corrosive

conditions

Information needed by electrician beforeconducting a survey

Type of equipment and its rating (operating

voltage and current)

IP classification (including measure of protect

against ingress of waterCircuit diagrams and/manuals for the equipment

Details of any modifications made

Means of isolations and location

Earthing arrangements

Type and size of cables

Details on the operations of protective devicesCopies of previous inspection reports and

repairs made/maintenance carried out


51/58

Robots, implications for safety and how risk to personnel can be reduced when

working with

Features of industrial robots that may have particularimplications for safety

Sudden, rapid or unexpected movementsAberrant behaviours e.g.. robot moving outside normaloperating parameters

Dropped loads or ejected materials people have to enter areato rectify

Software problems which are difficult to detect

Dangers associated with teaching robot e.g.. may require

close work with robot movingDangers from work being carried out e.g.. spot welding,stored energy

Dangers arising from maintenance activities e.g.. working inarea close, robot may continue working

Failure of perimeter sensors leading to robot collisions withpeople or other equipment

Reducing risk to personnel working in vicinity or with robots

Conduction risk assessment to identify hazards associated

with robots and those at risk, evaluate the risk and identify

controls required to reduce the risk to an acceptable level

(eliminate or reduce)

Restricting access by fixed fencing

Provision of interlock access point e.g.. pressure mats

Installation of light sensors e.g.. curtain or eye to detect

motion and stop robot (automatic guarding)

Provision of mechanical restrains

Use of audible start up warning

Procedures for restarting after interruption

Emergency stop systems

Introduction of safe systems of work e.g.. isolation lock out

tag out before maintenance activities commence

Training relevant people in hazards associated with robot andprecaution necessary

Introduction of monitoring system including audit and the

keeping of records of maintenance and defects

Maintenance program

Routine guard checking procedure


52/58

Robots, implications for safety and how risk to personnel can be reduced when

working with

Features of industrial robots that may have particularimplications for safety

Sudden, rapid or unexpected movements

Aberrant behaviours e.g.. robot moving outside normal

operating parameters

Dropped loads or ejected materials people have to enter area

to rectify

Software problems which are difficult to detect

Dangers associated with teaching robot e.g.. may requireclose work with robot moving

Dangers from work being carried out e.g.. spot welding,

stored energy

Dangers arising from maintenance activities e.g.. working in

area close, robot may continue working

Failure of perimeter sensors leading to robot collisions with

people or other equipment

Reducing risk to personnel working in vicinity or with robots

Conduction risk assessment to identify hazards associated

with robots and those at risk, evaluate the risk and identify

controls required to reduce the risk to an acceptable level

(eliminate or reduce)

Restricting access by fixed fencing

Provision of interlock access point e.g.. pressure mats

Installation of light sensors e.g.. curtain or eye to detect

motion and stop robot (automatic guarding)

Provision of mechanical restrains

Use of audible start up warning

Procedures for restarting after interruption

Emergency stop systems

Introduction of safe systems of work e.g.. isolation lock out

tag out before maintenance activities commence

Training relevant people in hazards associated with robot andprecaution necessary

Introduction of monitoring system including audit and the

keeping of records of maintenance and defects

Maintenance program

Routine guard checking procedure


53/58

Scaffolding, factors causing instability and principles of design and erection to

ensure stability

Factors that cause scaffolds to becomeunstable/collapse

Scaffold not erected as per original design

In-competent scaffold designers/erectors

Ground constructed on not being of load

bearing capacity

Scaffold foundation being undermined by

surface water or site works e.g.. excavation

Incorrect use of fittings and/or use of

damaged fittings

Standards were out of plumb or bent

Unauthorised/malicious alterations by

incompetent people

Overloading of scaffold e.g.. material

storage

Impact e.g.. load suspended by crane/hit by

plant vehicle

Severe weather e.g.. excessive wind loading

Principles of design and erection to ensuresafe/stable scaffold

Use of competent persons

Designed to withstand required loading

Constructed of sound materials & fittings

Setting standards on base plates

Ensure joints are staggeredFitting of longitudinal & diagonal bracing

Ledger braces at every other pair of standards

Vertical & horizontal ties no more than 8.5mapart and replaced by temporary ties if requiredto remove

Scaffold erected in position where traffic/plantimpact likely barriers should be erected(protection)

Ground erected on to have suitable load bearingcapacity

Inspections carried out at regular intervals i.e..not exceeding 7 days and after change inconditions e.g.. adverse weather conditions, afteralterations etc.

Do not load beyond design capacity

Pressure system

Is a system comprising one or more pressure


54/58

Pressure system

safety requirementsto be met before

commissioning

Siting of equipment to ensureprotection from vehicles

Separation from flammableatmospheres

Protection of public from emissionof noise

Competent person to undertake apre commissioning check

Establish maintenance andinspection procedures and writtenscheme of examination defines

System design issues

Adherence to standards

Capacity

Materials of construction

Layout features

Fitting of pressure gauges,warning systems

Relief valves and drain lines

Marking of safety related info e.g..safe working pressure

Suitable guarding

Certificate of conformity and CEmarked

Provision of information andtraining for operators includingsafety feature, limits and correctoperation of system

Is a system comprising one or more pressurevessels of rigid construction and anyassociated pipe work and protective devices

Pipe work with its protective devices to which atransportable gas container maybe connected

Pipeline and its protective devices which isliable to contain a relevant fluid. i.e.. steam, gasat a pressure greater than 0.5 bar above

atmospheric pressure when at a temp of 17.5 cor a gas dissolved in solvent at ambient tempwhich could be released from the solventwithout the application of heat


55/58

Trackers stability - will apply for most wheeled plant equipment

Factors that cause tractors tooverturn

Angle of slope operated on too great

Direction of travel on gradients

Uneven or soft ground

Speed of corner

Condition and pressure of tyres

Effects of trailers and other

attachments

Power take of seizure

Competence of driver

Minimising risk

Restriction of use on steep gradients

Operator training and awareness

Correctly maintained tyres and pressure

Fitting of wider tyres/additional wheels

Fitting of counter balance weightsRegular maintenance

Power take of fitted with shearing pins

Limit effects of over turning

Fitting and use of seat belt

Roll over protection e.g.. cage protections


56/58

Computer Numeric control systems (CNC) fitted to lathe

Additional risks

Increase in operation speed

Increase in noise

Possible unexpected movements

Errors in programming and software

Risk from teaching

Risk from operator unfamiliarity

Minimising risk

Risk assessment

Fitting of fixed or interlocked guards to

prevent access during automatic cycle

Provision of manual operation for setting

and cleaning operations e.g.. hold to run

system

Relocation of controls out of danger zone

Additional training for operators and

maintenance staff

Updating of the instruction manual for

use, cleaning and maintaining the machine

Conduct regular testing of the software

Conduct desk top survey (feasibility


57/58

Investigation into

dust allegation from

local village that

dust is from plant

you work in

Conduct desk top survey (feasibilitystudy) involving residents look at

Historical records

Weather patterns

Links with wind direction

Identification of potential otherdust sources in area

Check plant for obvious faults andconduct continuous monitoring(background)

Check supervisor reports over

period of alleged fall out forabnormalities in process/ checkmaintenance logs for break downe.g.. LEV systems

Consult and liaise with localauthorities/EA

Conduct analysis of dust collected

from village to establish if itmatches that produced from plant


58/58

Principle & Effect of

Vapour cloud

explosion

Confined e.g.. in a tank/vessel orunconfined e.g.. petrol releasevapour cloud travelling

Presence of flammable vapour atconcentration between LEL & UEL

Ignition source that exceeds theminimum ignition energy required

Effects of VCE

Vessel or containment ruptureresulting in rapid release ofliquefied gas

Projectile materials

Overpressure

Thermal effects

Effects of explosions UCVCE

Overpressure

Thermal effects

Emission of debris

People and property damaged dueto pressure wave and thermalradiation

Unconfined vapour clouds cantravel considerable distance beforeigniting (find ignition source) ormay be dispersed to aconcentration below LEL dependingon conditions e.g.. wind speeds,atmospheric pressure

Examples of VCE

Flixborough 74

Grangemouth

Buncefield

Revision Cards Unit C

Documents

Transcript of Revision Cards Unit C