Transcript Slide 1

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
Regs 1 -3
Reg 4 Systems, work activities & protective
equipment
1 Citation
2 Interpretation
3 persons with duties
Reg 16 Persons to be competent to
prevent danger and injury
•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
•An understanding of the concepts of
electricity and the risks involved in work
associated with it
•Knowledge of electrical work and
qualification in electrical principles
Reg 6 Adverse or hazardous
environments
•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
Reg 5 Strength & capability of electrical
equipment
•Experience
•Must be able to withstand effects of its
load
•Knowledge of systems of work & ability to
recognise risk & hazards
•Must be able to withstand effects of
transient or pulse currents
•Flammable or explosive atmospheres
•Physical attributes to recognise elements
of the system e.g.. not colour blind
Reg 7 Insulation protection & placing of
conductors
•Prevent danger from direct contact
through insulation etc
Reg 8 Earthing or other suitable
precautions
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
Electricity at work
regs 1989
•Purpose to prevent harm from indirect
contact e.g.. casings
Reg 9 Integrity of referenced conductors
•Allow persons to pass each other
•Ensure electrical continuity is never broken
Lighting should be adequate preference e to
natural then artificial
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
Reg 13 Precautions for work on equipment
made dead
•Identify the circuit, don’t 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
•Accompaniment
•Earthing
•Designated test areas
•PTW
•PTW
Reg 10 Connections – must have
adequate mechanical strength e.g..
plugs
Reg 11 means of protecting from excess
current e.g.. fuse, RCD
Reg 12 Means of isolation
Groups at risk
• Operators
Layout (Envelope)
Interlocked perimeter fencing
• Planning during design
• Positioned to prevent access to
dangerous parts
• Maintenance
engineers
• Minimise need to approach robot
• Teachers
• Good viewing arrangements outside
of enclosure
• Normally 2 meters high
• Rigid panels
• Adequate distance between robot &
enclosure
Behavioural - People
•Hazard aware
•Trained in procedures e.g.. entry,
emergency
•Adequately supervised
Preventative maintenance and
inspections
• Securely fastened to floor
• Infill suitable to protect from other hazards
e.g.. ejected materials
• Prevent trap points
• Adequate access to rescue injured
person
• Gates/access points to be interlocked
• Hinged/sliding interlocks
• Access only through interlocked
gates or similar
• Trapped key exchange
• Solenoid lock
Electro-sensitive safety systems
Robot Safety
• Used in conjunction with fencing
•Software checks to avoid aberrant
behaviours
• Photo cell device
•Stop devices
• Trip with use of light curtains
arranged
vertically/horizontally/diagonally
•Guard checks
•Integrity of parts for wear damage
e.g.. hydraulic rams
• Pressure mats around machinery
TEACHING
• Trip wires etc robot comes into contact
with a person should trip
•Remotely where possible
• All should require manual restart
•Slow mode when live
Entry Procedures
Positive stops
• SSOW defined/RA carried out
• Limits movement of robot
• Analysis of hazards in all possible
modes of operation
Emergency Stops provided at
• Defined limits to prevent trap points
• Control stations
• Avoid creating additional trap points
• Release of stored energy before
entry/work
• Teacher control pedestal
Brakes
• PTW
• All workstations
• Prevent danger of fall under gravity
• ISOLATION required
• Other positions as necessary
• Should be applied automatically when
machine stops
Reference – Supply of machinery
regs 1992 schedule 3
Consider
•Installation
•Use
•Maintenance
General
Controls
• Principles of safety integrations
• Safety & Reliability
• Materials & products used/created
• Control devices
• Lighting arrangements
• Means of starting stopping device
• Handling & Installation of machine
• Normal stopping
• Emergency stopping
•Decommissioning
• 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
Protection against mechanical
hazards
Machinery ‘Essential health
and safety requirements’
that should be addressed
•Stability/anchorage – e.g.. floor fixings
•Risk of break up during operation
•Falling objects/ejected parts
•Surface risk e.g.. sharp/hot/cold
• Instructions
•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
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
Key Factors
• Crane
Lift
• Lift
• Forensic evidence
• Load
• Weight
• Gravity – lifting point?
• Slinging method – appropriate for load?
• Type of lift
Crane
• Static
• Type –suitable for lift?
• Slewing
• SWL of crane
• Lift & Travel
• Alarm system working?
• SWL indicator/radius indicator
• Exceeded?
• Operational criteria e.g.. adequate
strength & stability
• Design characteristics
• Counter balance
• 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
• Out riggers
• Configuration for task e.g.. level
ground, positioning to load, distance
required to travel
• Settings & functionality of controls,
switches & alarms
• Maintenance & certification records
• Lifting history
Range of issues &
evidence to examine
during investigation of lift
op failure (crane)
Key Factors
Live Loads
• Dead load
• People
• Live load
• Furniture
• Dynamic load
• Solar radiation
• Vibration/sudden shocks
• Weather
• Atmospheric contaminants
Dead loads
• Material which buildings is
constructed from e.g.. columns,
beams, floors
• Equipment
Dynamic loads
Constantly moving and changing every
day
Dead loads & Live loads change
slowly and are called static loads
Other loads can change suddenly such
as wind gust, these loads are dynamic
• Timber decay
• Corrosion
• Subsidence
Solar Radiation
• Absorbed when it strikes a material
• Materials expand when warm
Subsidence
• Contract when cooling
• Signs of defects include
Factors Effecting
Structural Safety
• Semi random cracks in walls
• Sagging in arches/beams
• Fractures of pipe joints
• Builds over mine tunnels or large
holes can cause serious deformation
• Metal combines with oxygen in the
air to form rust
Rain/snow/hail
• Moisture greatest cause of
deterioration
Timber Decay
• Due to wet rot/dry rot/fungal attack
& insect attack
• Rain falling onto hot surfaces can
causes severe shock and result in
tension cracking e.g.. roof membrane
Vibration & Sudden Shocks
Corrosion
• Deterioration of timbers can
severely cases lead to building
collapse
• Solar radiation causes surfaces to
heat up quickly
• Rising damp causes flaking and
cracking
Atmospheric contaminants
• Combine with moisture to form acid
rains which attack materials
• Sulphur dioxide
• Carbon dioxide
• Oxygen
• Ozone
• Traffic/machinery
• Can effect foundations of buildings
• Buildings can be struck by
vehicles/plant
• Frozen water causes stresses &
cracks
Wind
• Moisture promotes rust in metals
• Physical damage
• Moisture creates environment for
fungal growth
• Dampness by driving rain moisture
into buildings
• Build of snow/ice on roofs increases
structural loading
• Can lift roof covering
Effects Fire on
materials
Steel
Concrete
Wood
• Will expand with heat
• Limited expansion
• Loss of strength normally @600
Celsius
• Cracks and spalls made worse by
expanding reinforcement steel e.g..
rebar
• Thin sections will burn promoting fire
spread
• Deform & Buckle
• When cooled will regain strength but
properties may have changed
• Acts as conductor transferring heat
thus spreading fire
• The charred surface of thick timber
will act as insulation to inner timber
• Poor conductor of heat
• Dependant on species
• Will have lost structural strength
when cool
• Generates smoke & allows surface
propagation of fire
Precautions to prevent
failure of materials
Steel
•Concrete cladding
•Compartmentalise to reduce
conduction
Concrete
Wood
•Selection of type and mix to
improve fire resistance
• Selection of thick timbers
•Increase thickness of concrete
from exposed surface to steel
reinforcement (rebar)
•Automatic cooling with sprinkler
system etc.
• Strength after burning depends on
original thickness and proportion loss
to fire
General precautions
•Sprinkle system
•Fire resistance cladding
•Early fire detection
•Control of ignition sources & reduction of fuel type materials – fire risk
assessment and adequate controls implemented
• Selection of timber e.g.. hardwood
burns slower than soft wood
• Treat with fire retardant substance
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
Reg 4(2) SSOW
Reg 4(1) Avoid if possible
Risk assessment to consider
Consider other options
• People conducting work e.g.. age,
experience, training
• Cameras
• Likelihood of flammable/explosive
atmosphere from previous contents
• Cleaning lances
• Robotic inspection
• Access/egress
Specified occurrence
• Contaminated air from previous contents
• Fire or explosion
• Build up of heat
• Loss of consciousness/asphyxiation
from gas, fumes or lack of oxygen
• Duration of activity
• Lack of oxygen
• Drowning
• Asphyxiation arising from free
flowing solid e.g.. mud slide
• Loss of consciousness arising from
high temperature
• Working at height within CFP
• Ingress of solids/liquids
Confined space
entry
• Impact of other plant
• Outside environment Weather, other
activities
• Isolations required
• Emergency situation
Reg 4(2) SSOW cont.
Control measures
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
• 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.
Last paper
Controlling pump rate
Complete containment of
flammable liquid, not leaks,
seals joints etc
• Speed slow – not to
propagate static build up
Avoid splash/spray filling
Worker involved trained and
competent in operation e.g..
aware of hazards and
precautions necessary
Earthing of all conductive
surfaces e.g.. tankers, pipe
work, containers e.g.. IBCs
Key factors to protect
against ignition from static
of a flammable vapour
during transfer of
containment of liquids
Over fill protection system
e.g.. high level indicator,
interlocked shut down
Use of inert gas blanketing
above the liquid
Keep at zero potential,
Earthing should be
interlocked to pump system
Provision of anti static
clothing including footwear
Implementation of a vapour
return system
Last paper
Key points
Controlled waste
• Controlled waste
• Household
• Duty of care ‘categories of
persons’
• Commercial
• Duty of care
Exceptions
• Industrial
• Agricultural
• Mines/Quarries
• Radioactive waste
Duty of care Categories of persons
Persons who
• Produces CW
• Imports CW
EPA section 34
Concepts of duty of
care
• Carries CW
• Stores CW
• Treats CW
• Disposes of CW
Exceptions of house holders
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
Automatic Fire Detection
Heat Detectors
Smoke Detectors
• Fixed temperature type
• Ionisation type
– Thermocouple detects when a set
temperature is reach
–Small radioactive source to ionise a
chamber into which smoke enters
during a fire. Detector reacts to
change in current caused by
neutralisation of ions by smoke
particles
• Rate of rise type
– Detects abnormal temp rises
(sudden)
– Electronic resistors
– Usually incorporate fixed temp
element as well
• Optical type
–Responds to the obstruction of a
focused light ray or the scattering of
light from an optical ray by smoke
Unsuitable for
•
Rapid heat rise workplace e.g..
laundrettes, steel manufactures
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 reason
Last paper
Raising the alarm
Publishing and training of
procedure
• Regular drills
• Documented
• Fire log book
• Consider any disabilities and
make provision for e.g.. visual
alarm for deaf people
Numbers of people to evacuate
& physical ability
• Contacting the emergency
service e.g.. interlocked alarm
system or manual call
•Distance of travel required
•Escape routes
•Alternatives routes
Accounting for people
Emergency light and signs
Liaison with emergency services
• Exits
• Numbers of people involved
• Escape routes
• Specific hazards in building
Issues to address
when planning a fire
evacuation
Refuges and safe havens
(muster points)
Prevention of re-entry
Training of fire wardens
• Zoning
Equipment and security
• Areas of responsibility
• Equipment may need shutting
down safely
Roles and responsibilities
• Security could be an issue
after evacuation
• Staff
• Managers
Key principles
• Dust control
• Ignition source control
• Mitigation of explosion effects
• DSEAR regs
Ignition control
• Zoning
• No smoking policy
Mitigating effects of explosion
• No mobile phones
• Equipment able to withstand
explosion
Dust control
• Damping down
• Provision and use of anti
static clothing and footwear
• Extraction of dust at point of transfer
(LEV)
• Earth bonding of equipment
• Bursting disc on vessels
• Assessment in compliance
with DSEAR regs
• Suppression – inerting
• Interlock device to prevent
overfilling of vessels
• High standard of house keeping
• Ensuring that systems are sealed
where possible
• 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
Reducing risk of dust cloud
explosion and mitigating
explosion effects
• Venting and explosion panels
• Compartmentalisation – minimise
effected
Consider automated system
(robotic to almost eliminate
pedestrians requiring access
Segregate pedestrians from
vehicles with the use of fixed
barriers
Where possible re-route
pedestrians away from
vehicle movement area e.g..
elevated corridors
Ensure lighting is adequate
and suitable for tasks carried
out
Separate access & egress points
for vehicles/pedestrians
Create safe passing places
Design features to
reduce risk of
vehicle/pedestrian
collision
Introduce safe crossing
points e.g.. zebra crossing
Avoid creation of blind bends
if unavoidable install wall
mounts mirror (convex) to
improve visibility
Allow sufficient space for
vehicles to operate
Where possible design
routes such to
eliminate/reduce the need for
reversing
Direction of vehicle
movement control e.g.. force
one way traffic
Mechanical hazards
• Vehicle impact
• Plant equipment nearby
• Abrasion from operate
equipment
Weather conditions
• Rain – moisture entering
• Freezing leading to crack
through expansion
High/Low temperatures
Aspects of a working
environment which
increase electrical risk
• Heat
• Humidity
Corrosive atmospheres
leading to corrosion of parts
Flammable/explosive
atmosphere
Intrinsically safe
Flame proof
• Restriction of electrical energy in
equipment, insufficient to create
heat/sparks
• 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
• Faults may increase energy levels above
safe limit
• May not be suitable for use in areas with combustible
powders of dust. May require special measure to prevent
ingress of water
Inform of any
significant/unusual residual
risks
Duties apply at all times e.g..
appointing of CDM coordinator if notifiable
Provide info with the design
to assist clients, contractors,
designers e.g.. notes for
drawings, rational behind
design decisions
Take into account Workplace
(HS&W) regs when
designing workplace
structures
Conduct risk analysis of
major design e.g..
HAZOP/FMEA
Duties of designers
under CDM2007
Ensure 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
Avoid foreseeable risks
(construction and use)
SFAIRP during design by
•Eliminating hazards where
poss.
•Reduce remaining risk
•Give collective risk
reduction measures priority
over individual measures
Co-operate with CDM co-ordinator &
other
Provide information for h & S
file
Regular maintenance and
safety inspection e.g.. guard
check
Safe operation and
adjustment of top guard
Effective guarding of blade
under bench
Adequate lighting and saw
suitably fixed to floor
Provision of emergency
stops and means of isolation
Use of push stick to feed
materials being cut
Safe operation of bench
mounted circular saw
Ensure that the riving knife is
correctly positions through
risk assessment
Sufficient space around
equipment kept clear of
obstructions
Use of appropriate PPE e.g..
hearing protection/goggle,
dust mask
Ensure that operators are
suitable trained and
experience to use the saw,
also ensure appropriate level
of supervision
Provision of LEV to remove
dust
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
Excessive Stress
• Ductility – amount of stretch before a
material ruptures
Abnormal external loading
• Usually result of single stress over
load
• Struck by something e.g.. vehicle
• Materials can balloon due to
excessive pressure
• Explosion
• FLT/Fuel tankers
Hydrogen attack
Over pressure
• Hydrogen seeps into gaps in
molecular frame work
• Catastrophic results e.g.. vessel
rupture
• Causes stresses within framework
• Failure of relief valves can cause
• Examples are cathode reaction,
electroplating
Pressure systems
causes of failure
• Normally systems tested to 3 times
normal operating pressure
Creep
Overheating
• Under constant load
• Can occur if alarms/controls fail
• Deforms over time (plastic)
• Causes rise in pressure
• Temperature is important, materials
determine working temperatures that
can be used
Mechanical fatigue & Shock
Brittle fracture
Thermal fatigue & Shock
• Fracture without deformation
• Shock is sudden change in temp of
water
• Brittle materials are strong but not
resistant to cracks
• Impact loading causes e.g.. rapid
temp changes, pressure differences
• High tensile & residual stresses
promote
• Causes rapid expansion/contraction
of system components
• Leads to fatigue and material stress
ultimately failure of system e.g..
leaking pipes, fracture of vessels
• 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
Key points
• Design
• Operation
• Inspection/Maintenance
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)
Operation
• Gauges
• Use within performance envelope
• Level Controls
• Operators trained and experience to
identify errors and prevent faults
through error arising
• Blow down valves
• Pressure gauges
• Aware of safe operating limits
• Scheme of examination
• Equipment marked with operating
pressures/temperatures max/min
• Quality control
• Filtering/treating of water (boilers)
Technical & procedural
measures to minimise
likelihood of pressure
system failure
Inspection
• Written scheme of examination –
statutory
• Pressure vessels
• Pipe work and valves
• Protective devices
• Pumps and compressors
• Prepared by competent person
• NDT/examination
Properties of LPG
• Flammable at standard temp &
pressure
• Denser than air
• Liquid form floats on water
• LEL is reached in small
concentrations
• Can cause suffocation in high
concentrations
Control of ignition sources
• No smoking
• Storage of cylinders away from
potential ignition sources e.g..
fabrication shop
• Control of mobile phones
Concrete level floor, surrounding
area kept free of vegetation (not
with use of oxidising week killer
e.g.. sodium chlorate
• Storage area regarded as zone 2
so only zone 2 IS rated electrical
equipment to be used
• Signage stating highly flammable
• Dry powder fire extinguisher
located close to storage area
Stored away from excavations,
drains, pond, rivers, cellars at least
3m
Any store room must be noncombustible or fire resistant and
ventilated with and explosimeter
installed
If more than 400Kg stored must
have 2m high mesh fence and
cylinders at least 1.5m away from
fence with 2 exits
LPG in cylinders
precautions
(storage)
Protected from elements were
possible
Empty cylinders stored separately
from full cylinders, caps fitted to
valves. Well ventilated
Stored away from any oxygen
cylinders. oxidising substances
Storage compound designed to
prevent vehicle impact
Cylinders stored in upright position
Key points
• Instability
• Training
• Refresher training circumstances
Causes of instability Lateral (side
instability)
• Insecure load
Refresher training appropriate
• Operator not used truck for some
time
• Drive laterally on slope (angle of
slope, elevation of load
• Hitting obstruction e.g.. curb
• Been involved in accident/near
miss
• Uneven ground
• Developed unsafe practices
• Poor tyre condition/uneven
pressures
• Change in working practice
• Cornering (fast, sharp)
• Best practice every 3 years or as
per company policy
Causes on instability Longitudinally
(Front to back instability)
• Overloaded vehicle
FLT safety
• Incorrect positioning of load on
forks
• Load slipping forward
(inappropriate tilt of mast
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
• Driving with load elevated
• Changing tilt
• Driving forwards down slops
• Driving backwards up slopes
• Sudden braking
• Striking overhead obstruction
Key points
• Fuses
• Miniature circuit breakers
• Residual current devices
• Reduced low voltage systems
• Precautions to be taken
Fuse
• Protects systems not people normally
Miniature circuit breaker
• Prevents overloads of electrical system
and overheating of electrical wiring
• Close tolerances for design
current flow and speed of
operation
• Limits shock under severe fault
condition
• Limits over currents
Precaution to be taken when maintaining
or repairing electrical systems
• Does this by the heating effect of electric
current which melts the metal link if
current exceeds the design value
• Remains broken until replace
• Provide visual detection following
operation (e.g.. switch to off
position
• Need to be reset after fault
detection
• Are reliable
• Design to protect system
•Identify equipment to be worked on
•Obtain system drawings & information
•Consider whether work can be done
dead SSOW for dead:
• Isolation/lock off
• PTW
• Proved dead
• Test test equipment
•If work required is live SSOW:
Methods and devices
designed to improve electrical
safety + precautions to be
taken when maintaining or
repairing systems
• Screening of conductors near
work
Residual current devices or earth leakage
circuit breakers
• Testing live conductors through
holes with probes
•Shock limiting device not system
protection
• Use of suitable test equipment
• Have testing arrangements in
place for testing equipment
• Consideration of accompaniment
• Consideration of insulated tools
• Adequate space
• Adequate lighting
•Shock is still received but time reduced
Reduced voltage system e.g.. 110V
• Transformer
•Monitors balance of current in line and
neutral
• Supply centre tap to earth consist of
•Operates on earth leakage fault
• Earthed systems
• Class 1 equipment
• Double insulated class 2 equipment
• Required procedural measures to be followed
•Live and neutral disconnect from local
power supply
Design
Operation
Maintenance
• Material to be used for vessels and
pipework
• SSOW
• Arrangements for examination and
inspections
• Suitable to withstand corrosive
nature of substances
• Layout of facility
• Segregation between acid/alkalis
e.g.. compartmentalisation
• Design and position of inlets
• Prevent cross connection
• Operation of equipment
• Emergency procedures e.g..
spill response
• Training
• PTW system
• Isolation procedures
• Cleaning prior to work e.g.. purge
• Tanker drivers
• Regular cleaning of bunds
• Operators
• Provision of training to maintenance
staff both maintenance and
emergency
• Provision of PPE e.g.. chemically
resistant suits, gloves, full face visor
• Bunding of tanks
• Separate bunds
• Capacity 110% of largest container
min
• Bunded sealed with appropriate
material (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 of
pipes
• Emergency arrangements e.g.. drench
water safety shower
Safety provisions required for
receiving and storing acids and
alkalis
Chemical changes involve heat
Temperature Increase speeds up
reaction – Le Chateliers principle
• Exothermic - Evolutes
If the heat released from reaction is
not controlled/removed reaction will
speed up exponentially
• Endothermic - Absorbs
Can result in
• auto ignition explosion
• Catastrophic over pressure
resulting in loss of containment
e.g.. vessel rupture and toxic
release
Operational features to prevent
• High calibre of operator experienced
and appropriate level of qualification
to operate process
• Violent boiling
• Secondary competing reaction
Runaway reactions
• Ensure that maintenance
activities/raw material handling don’t
introduce potential catalysis into
reaction
Causes
Design features to prevent
• Failure of temp control (reaction
cooling)
• Conduct HAZOP study
• Strong exothermic reaction
• Appropriate temperature control system
e.g.. matrix cooler
• Presence of containment catalysis
(speeds up reaction)
• 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
• PRV’s, weighted lids to realise pressure
• Agitation of liquids to promote even temp
distribution
Cylinder/container containing
flammable gas under pressure e.g..
butane pressure turns gas into
liquid state
Valve opened reduces pressure
turning liquid into gaseous state
Examples of incidents
San Carlos
Cylinder exposed to heat source
e.g.. caught in a fire liquids absorbs
heat
• Crashed over loaded road tanker
• Explosion
• 216 Dead
Mexico city
BLEVE
Liquids starts to vapour and is
vented off
Sudden release of contents
resulting in
Liquid level falls heat continues
•Blast wave (low)
•Radiation (thermal) high
•Missiles travelling long distances
Substantial thermal heat sever
burns e.g.. LPG cylinder BLEVE has
serve burn range of 35m
Area of cylinder just above liquid
level starts to weaken/thin with heat
Area unable to hold internal over
pressure and ruptures
Identify recycling opportunities at
all stages of process
Substitute process materials for
ones that give rise to non
hazardous waste
Explore becoming licensed to save
cost e.g.. EA permit
Explore other disposal means
(incineration, liquefied waste to
sewer)
Reducing cost and
environmental impact
of hazardous waste
(sludge)
Exchange waste streams to other
companies which could use waste
as raw material e.g.. waste solvents
to paint producers
Improve production efficiency to
produce less waste
Treat waste on-site to reduce
quantity (De-watering)
Treat waste to reduce hazardous
properties e.g.. ph balancing
Selection of waste contractors that
can process the waste
Last paper
Purpose
Check for faults (e.g.. cracks) in
components before they develop
into total failure without affecting
integrity of the component
Dye testing
Impact (tap testing)
• Put dye on
• Strike surface
• Dye penetrates making cracks visible
• Cheap & simple (pro)
Other techniques
• Pneumatic testing
• Doesn’t detect sub surface faults
(con)
• Hydro testing
• Not totally reliable (con)
• Can be enhanced by using
fluorescent penetrate and UV source
Ultrasonic Technique
• Penetrate may be toxic (con)
• Short pulses of high frequency
ultrasound are used
• Need good eyesight
• No indication of where fault is
located (con)
• Relies on individual skill (con)
• Coat surface with magnetic power
or liquid
• Surface and sub-surface defects
• Quick to perform
• Cheap (pro)
Magnetic particle
• Reflected waves detected and shown
on digital display or oscilloscope
• Only requires one side of joint
• Changes in pitch of reverberant
sound
• Simple & Quick
NDT
• Suitable for most environments
• High level of expertise required
• Very sensitive to surface cracks
• Interpretation of results can be
difficult particularly on inside of
vessel
• Coupling equipment onto rough
surfaces can be difficult
Radiography
• X-rays/Gamma rays penetrate item and
leave an image on film
Eddy current testing
• Surface and near surface crack detection
• Electromagnetic method/instrumentation
• Defects are shown up by differences in the
intensity of the radiation striking the film
• Can be used to verify materials heat treat
condition
• Detects internal defects and a permanent
record is created
• Can be automated (pro)
• Expensive
• Can suffer from spurious defect
indications
• Bulky equipment
• Doesn’t work on non-conductive materials
• Present radiation hazard and tight controls
are required
• Relatively expensive and requires skilled
operator
• Skilled radiographers are needed
Consideration of flammable
atmospheres etc EX rating
Maintenance, cleaning and
testing considerations
Availability of natural light
Psychological effects
Compliant with workplace (health,
safety & welfare) regs
Illumination ratio
Level of luminance
H & S Issues to identify
during a lighting audit of a
factory
Emergency lighting
Requirements for pedestrians/vehicles
Close working tasks
Lighting fort non-daytime
external areas
Equipment lighting to comply
with PUWER requirements
Task specific lighting
Avoidance of stroboscopic effects
with regard to rotating machinery
DSE work station lighting
Avoidance of glare
Access & Egress
Emergency arrangements
• Alarm
• Muster points
• Escape routes
• Maintenance workers
• Pedestrians
• Building workers
• Vehicles
Traffic management
Public safety
• Deliveries
• Falling objects
• Plant
• Screening
• MEWPS etc
Storage of materials
• Hazardous
• Flammable
• Housekeeping
• Segregations/barriers
Safety aspects to consider
before starting external
maintenance/construction
works on build with public
facing front (footpath) work
includes roof
• Lay down areas
• Security
• Fencing
• Dust damping
• Noise levels
Building workers safety
• Safe systems of work
• Provision of PPE
• Fall protection
• Scaffolding
• Edge protection
Welfare facilities
Plant and equipment requirements
• Signage
• Washing
• Suitability
• Toilets
• Availability
• Hazardous materials present e.g.
asbestos
• Rest/eating etc
Benefits of regular drills
• Compliance with legal
requirements FFRO
• Efficient evacuation in future
• Highlights deficiencies in alarm,
procedure and evacuation
• Allow practise of scenarios such
as abnormal normal route use etc
• Refresh staff training and
awareness of procedure
Fire Alarm Design/maintenance
• Quiet
• Does not extend into all parts
of building
• Poorly maintained sounders
• Faults within infrastructure
leading to partial failure in
some areas
Deficiencies in procedure
• Difficult to understand
• Poorly communicated
• Not exercised
• Poorly planned escape routes
Factors that could
contribute to a delay in
evacuation + benefits
of regular drills
Human factors
• Hearing disabilities
• Belief that false alarm
• Untrained staff
Execution of procedure
• Delayed response to alarm
• Staff not reacting quickly
• Finishing of phone calls
• Belief that above evacuating
• Switching off equipment
• Waiting for direct notification
e.g.. phone call
• Fire Marshalls not following
procedure
• Routine violations
• Blocked escape routes
• Staff not trained
• Poor response perhaps many
false alarms have occurred in past
Introduction of Automated Guided Vehicle to
Warehouse
Risks Reduced
• Manual handling
• Pedestrian/vehicle collision
• Racking Collisions
• Falling objects less likely to
contact 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 for
equipment
• Software failure
Planning & Organising
• Consider work to be carried out
and 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
Working area
• Emptied
• Excluding non essential personnel
• Locked off to prevent filling
movement of parts
• Erecting barriers
• Sighting of warning signs
Working at height
• Use of platforms
• Handrails
• Toe boards
• Harnesses if required
• Protection of fragile sections of
silo top
Precautions to be
taken before &
during repair work
of a 15m high grain
silo on farm (with
welding required)
• Residue removed before hot
works
• Damped down
• Signage erected of work in
progress etc
Confined space entry
• PTW control
• Ventilation
• Trained staff
• Emergency rescue plan defined
and trained
• Ensure suitable access and
egress
• Oxygen monitoring
MEWPS
Hazards
Requirements for safe use
•
•
•
•
•
•
•
•
•
Falls from height of persons/materials
Instability of vehicle e.g.. uneven
ground
Being struck by other vehicles
Trapping & impact hazards
Mechanical failure
Contact with over head power lines
Exposure of workers to adverse
weather conditions
•
•
•
•
•
•
•
•
•
Selection of trained competent operators
Persons may be connected to MEWP with
fall 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 of
outriggers where installed
Prevent of use in adverse weather
conditions
Not exceeding SWL
Regular inspections & maintenance
Ensure trap points are guarded
Ensure used in locked position
Prohibit transfer of people/materials whilst in
raised position
To supply machine
under SMSR1992
process
Satisfy Essential health and safety
requirements and be safe
•Safe and reliable control devices
including normal operation and
emergency controls
•Stable
•Protection against mechanical
hazards e.g.. moving parts guarded
Satisfy requirements of
EHSR
Responsible person to
prepare technical file
•Protection from other hazards e.g..
vibration, electricity & noise
•Maintenance activities
•Adequate indicators e.g.. alarms
and warning light etc
Preparation of technical file
•Detailed drawings
•Calculations, test reports
Responsible person to
ensure machine meets
requirements of other
EC directives
•Description of methods used to eliminate
hazards
•Machinery RA
•Instruction draw up in accordance with
provision of information
Issue a Declaration of
conformance
Fix the CE mark in a
visible, legible and
obvious manner
Last paper
Determine appropriate
frequency of inspection for each
item based on factors affecting
level of risk e.g..
•Type of appliance
•Protective systems used
•Use
•Frequency of movements
Inventory of all equipment
requiring examination and
test to be made and unique
means of identification
e.g.. number system
•Earth boning
•Age
•Environment which appliance
used in
•Experience and competence of
user
•Historical information and
manufacturers
recommendations
Factors to consider
when devising
scheme for PAT
testing
Criteria for each type of
examination defined including
issues such as
•Competence of the tester
•Calibration and maintenance of
test equipment
•Format of records to be kept
•Results of tests and
examinations
•Systems to identify and remove
from use equipment that is
found to be faulty
Electricity at work regs and HSE
published guidance
Sources of Ignition from diesel powered vehicles and possible protection to
minimise risk of explosion in flammable atmosphere
Sources
• Flames/sparks from exhaust/inlet
systems
• Sparks from vehicle electrical
system
• Static build up from over
speeding/loading the engine
• Hot parts e.g.. exhaust
Protection
• Fit spark/flame arrestors preventing
flashback to atmosphere if drawn into
inlet system plus prevent any sparks
from escaping system
• Engine and exhaust system design to
ensure surface temps are below
ignition temp of atmosphere
• Use of water jacket around hot parts
• Electrical equipment on vehicle
suitable for zones 1 or 2 where
possible
• Speed limiters to prevent speed at
which static could build up
• Use of electrically conductive materials
for parts e.g.. tyres to reduce static
build up.
Bunding to contain spills
Security features such as locks,
alarms, and signage
Facility to collect & dispose of
spillages e.g.. spill kit
Emergency lighting/appropriate EX
rated electrical equipment e.g.. zone
2 rated lights
Sprinkler systems/fire extinguishers
Adequate access and egress e.g.. 2
points of entry/exit including ramp
to facilitate drum handling
Building constructed of fire
resistant materials
Key safety features
of building used to
store highly
flammables
Mean of segregation of materials
e.g.. low walls/dividers, cabinets
High and low level ventilation
Adequate distance from other
buildings
Roof lightweight and/or blast panels
Impermeable floor
Capacity of water required and
adequacy of existing supply
Design of pump system e.g..
diesel back up if electrical pump
installed
Provision required for testing
and maintenance
Means of activating system
(fragile bulbs or detector
activated
Provision of water run off
Provision of fire stopping water
curtains to prevent fire spread,
compartmentalisation
Design factors to
consider when
providing a sprinkler
system
Linkage of system to alarms
Spray pattern required
Height of any storage racking
and distance from sprinkler
heads, possible protection from
vehicle movements e.g.. FLT
tines
Area to be covered
Presence of substances which
react violently with water
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
Notification of HSE under CDM 2007
regs
Identification of competent
demolition contractors
Site traffic management if required
If building partially collapsed
already devise method for
demolishing to avoid premature
collapse of the remainder
PPE required for workers e.g.. hard
hats, ear protections safety boots,
protective clothing, eye protection
etc
Protection of nearby
buildings/business/properties
Welfare facilities provision e.g..
toilets, wash and rest facility plus
maybe lay down area for
contaminated clothing
H & S issues to be
considered when
planning demolition
of building
Protection of public e.g.. barriers,
signs, security
Precautions to prevent people or
objects falling e.g.. scaffolds, edge
protection
Control of noise
Identification of hazardous
materials, control of dust and safe
removal of waste from site – use of
licensed carrier etc
Selection of and Inspection,
maintenance of plant and
equipment to be used
Identification of buried and/or
overhead services e.g.. power
cables, gas pipelines
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
Explore possibility of re-routing
cables or making dead
Consult with utilities supplier before
taking any protective measures
Warning signs and protection for
public if necessary
Supervision and hazard awareness
training for workers e.g.. toolbox
talk on hazard associated with cable
and what measure need to be taken
to avoid
Precautions to be
taken when working
near an overhead
electrical supply
Identification of safe working
distance i.e. 9 m if wooden or steel
poles 15m if pylons plus length of
jib or boom if cranes/excavators are
to be used
Use of barriers, marking tape and
bunting
Safe systems of work to be defined
and implemented
Use of goal posts and/or tunnels
Height restrictions on plant
Planning and assessment for
development of electrical supply by
a competent person
Safe positioning of transformers
e.g.. protection from plant/vehicle
impact, barriers to prevent workers
accessing area
Use of competent persons for
installation work of electrical supply
Development of safe systems of
work
Precautions to ensure
safe provision & use of
electricity on construction
site (feed taken from
overhead lines)
Routing, marking and protection for
cables
Use of protective devices e.g..
reduced low voltage systems (110),
RCD’s and double insulated
equipment
Arrangements for testing and
maintenance of portable equipment
Arrangements for inspection and
maintenance of the fixed supply to
include earth bonding checks
Fatigue failure
• Crack propagation from points of stress concentration
(e.g.. groves, weak weld points), fluctuating stress final
failure may be ductile or brittle
Buckling (Compressive force)
• Surface occlusions/damage
• Buckling – yield of one side of
structural member under axial
compressive loading
Brittle failure
• Choice of material
• Factors contributing
• brittle fracture, no apparent plastic
deformation takes place before fracture
Factors which promote brittle fracture
• Low temperature
• Inherently brittle material (cast iron)
• Impact or snatch loading (does not give
material time to react
• Residual stress imposed through manufacture
• Excessive/non uniform loading
• Corrosion, temperature
• Weakening due to removal of
cross members
• Factors contributing
• Measures to take to prevent
• Use of out of true members e.g..
scaffold tube at incorrect angle
i.e.. not 90 under load
• Design spec appropriate
• Quality assurance on manufacture
• Excessive temperature
• Assembled according to spec
• Measures to be taken to prevent
• Correct use – avoid misuse e.g.. over ,loading
• Design/material selection
• Maintenance/testing NDT
• Avoid overload work within spec
• Temp control
• Maintenance/testing NDT
Component failure
Ductile Failure (stretch)
• Ductile failure in metals occur when the yield stress of the
material has been exceeded by the material being placed in
tension (stretched). The metal moves from it’s elastic region
into it’s plastic region and loses its shape. There is a
reduction in cross sectional area at failure point. The failure
will appear as a ‘cone / cup’ at 45 degrees to the load along
the grain boundaries
• Factors contributing
Creep
• Gradual yielding of material under stress close to elastic
limit (undergoes plastic deformation
• Factors contributing
• Continuous loading
• High temperature
• High temp e.g.. hot pressurised pipes, turbine
blades
• Over loading
• Overloading
• Design inappropriate
• Design spec etc
• Measures to be taken to prevent
• Measures to be taken to prevent
• Temp control
• Temp control
• Selection/design of materials
• Selection/design of materials
• Maintenance/testing
• Maintenance/testing
• Operate within spec limits of equipment
• Operate within spec limits of equipment
Gamma radiography uses the transmission of gamma
rays from a sealed ionising radiation source (isotope)
through a test object onto a film placed on the opposite
side. The film records the intensity of the radiation
received and since cracks and flaws are hollow, a
greater intensity of rays pass onto the film showing up
defects as darker regions
Advantages
Permanent record produced.
• Can be used to test most materials
Gamma
Radiography
• Internal defects can be identified
• Coupling with the surface of the test
piece is not required
Disadvantages
• Poses a radiation exposure hazard to operators requiring
specific SSOW to be implemented
• Can be time consuming due to application to HSE each time
test 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
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 of
nitrogen from burning of fossil
fuels
– Sulphur dioxide/sulphur
compounds when coal or oil is
burned
• Other pollutants
– Soot & coal dust from
incomplete combustion
– Solid waste from coal & oil ash
– Acid & alkali effluents from
water treatment process
– Emissions from vehicles
delivering fuel to site same for
ships
Abnormal operations
• Leaks
– Oil storage tanks
– Gas supply pipelines
– Acid/Alkali storage tanks
• Spillage of chemical from road
tank accident
• Oil slicks from ships during
offloading or major disaster
e.g.. sinking
• Fire leading to fire water run off
during fire fighting
Design of basket
• Constructed for task
intended
• Not exceed the width of FLT
• Toe boards/guard rails
installed
• SWL indicated on basket in
either weight or no. of people
possible to carry, not
exceeding 50% of FLT SWL
Trained and competent operator in
basket, aware of hazards associated
with use
Competent FLT driver
• Guards fitted to protect
against moving parts of FLT
e.g.. chain
Factors to ensure
safe use of FLT
man basket
Anchorage point in cage and
harness fitted and connected to
persons in basket
Basket maintained and inspected at
least every 6 months
FLT to be parked on firm, level
ground, brake applied, driver in
truck
Cage securely fixed to forks and
truck not moved during activity
Barriers positioned around work
area preventing collision from other
vehicles and protect others against
falling objects from basket
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 to
prevent such an incident
• Adequate segregation between
adjacent tanks
• Separate bunds for each tank
• Interlocked pumping system with
high level alarms min double redundancy
of alarms
• Level detection
• Vapour detection system fitted in
bunds
• Remote shut down system
• Good earth bonding
Measures to mitigate the effects
• Fixed foam installations capable to
spray the surface of pool in the
bunded areas
• Installation of foam monitors capable
of reaching top of tanks
• Radiation walls between tanks/bunds
to prevent other tanks from being
heated
• Adequate supply of fire water
• Installation of remote pumps to empty
affected tanks
• Easy route of access for fire fighters
• Provision of drainage interceptors to
minimise enviro affects of fire water
run off
• Regular draining and cleaning to
remove rainwater from bunds
• Provision of site based emergency
response team.
Design
Fixed guard
Defined in BSENISO12100 as a guard fixed in
such a manner (e.g.. by screws, nuts, welding)
that can only be removed or opened by the use
of tools or destruction of the affixing means. It
provides protection against mechanical hazards
when infrequent or no access is required during
normal operation of the machine. Acts as a
fence between people and dangerous machinery
parts
• Material of construction sufficiently
robust to withstand workplace
rigours and contain any ejected
materials
• Should allow sight of process if
required
• Method of fixing should require
special tool to removed e.g.. torque
bolts
• Ensure that any necessary
openings provide enough distance
from hazards to prevent harm
• Guards reverberation exacerbating
noise problems
Fixed guards factors to
consider in design and
use to ensure people are
adequately protected
Use
• Monitoring and supervision to
ensure guards are not
removed/tampered with
• SSOW fir carrying out
maintenance operations with
guards removed
• Guard check procedure to ensure
guard is kept in maintained
condition
• Provision of information and
training for operators and
maintenance staff detailing the
hazards associated with guard
defeats and other SSOW
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
Information needed by electrician before
conducting a survey
•Type of equipment and its rating (operating
voltage and current)
•Damaged sockets and switchgear
•IP classification (including measure of protect
against ingress of water
•Covers missing from junction boxes
•Circuit diagrams and/manuals for the equipment
•Incompetent workmanship and
inadequate excess current protection
•Details of any modifications made
•Exposed conductors due to damaged insulation
from corrosive
•Earthing arrangements
•Short circuits caused by ingress of fluids
•Details on the operations of protective devices
•Corrosion of system parts
•Copies of previous inspection reports and
repairs made/maintenance carried out
•Unsuitability for use in wet & corrosive
conditions
•Means of isolations and location
•Type and size of cables
Robots, implications for safety and how risk to personnel can be reduced when
working with
Features of industrial robots that may have particular
implications 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 require
close 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 and
precaution necessary
•Introduction of monitoring system including audit and the
keeping of records of maintenance and defects
•Maintenance program
•Routine guard checking procedure
Robots, implications for safety and how risk to personnel can be reduced when
working with
Features of industrial robots that may have particular
implications 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 require
close 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 and
precaution necessary
•Introduction of monitoring system including audit and the
keeping of records of maintenance and defects
•Maintenance program
•Routine guard checking procedure
Scaffolding, factors causing instability and principles of design and erection to
ensure stability
Factors that cause scaffolds to become
unstable/collapse
Principles of design and erection to ensure
safe/stable scaffold
•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
•Use of competent persons
•Designed to withstand required loading
•Constructed of sound materials & fittings
•Setting standards on base plates
•Ensure joints are staggered
•Fitting of longitudinal & diagonal bracing
•Ledger braces at every other pair of standards
•Vertical & horizontal ties no more than 8.5m
apart and replaced by temporary ties if required
to remove
•Scaffold erected in position where traffic/plant
impact likely barriers should be erected
(protection)
•Ground erected on to have suitable load bearing
capacity
•Inspections carried out at regular intervals i.e..
not exceeding 7 days and after change in
conditions e.g.. adverse weather conditions, after
alterations etc.
•Do not load beyond design capacity
Pressure system
• Is a system comprising one or more pressure
vessels of rigid construction and any
associated pipe work and protective devices
• Pipe work with its protective devices to which a
transportable gas container maybe connected
• Pipeline and its protective devices which is
liable to contain a relevant fluid. i.e.. steam, gas
at a pressure greater than 0.5 bar above
atmospheric pressure when at a temp of 17.5 c
or a gas dissolved in solvent at ambient temp
which could be released from the solvent
without the application of heat
Provision of information and
training for operators including
safety feature, limits and correct
operation of system
Siting of equipment to ensure
protection from vehicles
Separation from flammable
atmospheres
Protection of public from emission
of noise
Pressure system
safety requirements
to be met before
commissioning
Competent person to undertake a
pre commissioning check
System design issues
• Adherence to standards
• Capacity
• Materials of construction
• Layout features
• Fitting of pressure gauges,
warning systems
• Relief valves and drain lines
Establish maintenance and
inspection procedures and written
scheme of examination defines
• Marking of safety related info e.g..
safe working pressure
• Suitable guarding
• Certificate of conformity and CE
marked
Trackers stability - will apply for most wheeled plant equipment
Factors that cause tractors to
overturn
•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 weights
•Regular 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
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
study) involving residents look at
•Historical records
•Weather patterns
•Links with wind direction
•Identification of potential other
dust sources in area
Check plant for obvious faults and
conduct continuous monitoring
(background)
Consult and liaise with local
authorities/EA
Conduct analysis of dust collected
from village to establish if it
matches that produced from plant
Investigation into
dust allegation from
local village that
dust is from plant
you work in
Check supervisor reports over
period of alleged fall out for
abnormalities in process/ check
maintenance logs for break down
e.g.. LEV systems
Confined e.g.. in a tank/vessel or
unconfined e.g.. petrol release
vapour cloud travelling
Presence of flammable vapour at
concentration between LEL & UEL
Examples of VCE
• Flixborough 74
• Grangemouth
Ignition source that exceeds the
minimum ignition energy required
• Buncefield
Principle & Effect of
Vapour cloud
explosion
Effects of VCE
• Vessel or containment rupture
resulting in rapid release of
liquefied gas
• Projectile materials
• Overpressure
• Thermal effects
Effects of explosions UCVCE
• Overpressure
• Thermal effects
• Emission of debris
• People and property damaged due
to pressure wave and thermal
radiation
Unconfined vapour clouds can
travel considerable distance before
igniting (find ignition source) or
may be dispersed to a
concentration below LEL depending
on conditions e.g.. wind speeds,
atmospheric pressure