Safety Training Presentation No 3
Electrically isolate and lock off when power is not required
and when working close to unguarded machinery
V5-11 November 2012
Accidents
Over the last 20 years there have been 12 fatal
accidents within the UK lift and escalator industry
How have the fatal accidents occurred?



Falling from height
Crushing/ struck by moving equipment
Electricity
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3
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
The Risk…




Approximately 20 fatalities per year in UK (all industries).
Electrical injuries caused by a range of voltages –
dependant upon circumstances
230V can, and does kill…
Equipment flashovers, burns, loss of muscle control,
consequential falls from height etc.
4
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
The Risk…





Shock is the effect of current flowing through the body
Current does the damage
Causes muscles to contract, tissue damage and internal
burning
Can cause cardiac arrest and respiratory failure
The higher the current: the shorter the duration for injury
5
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
The Risk…
 Threshold of sensation: 0.5mA
 Threshold of pain: 5mA
sufficient to cause spasms,
 ‘Let-go’ current ( but still allowing ‘let go’ ): 10mA
 Ventricular fibrillation (heart spasms): 50mA
 60W light takes 250mA
Source: DD IEC/TS 60479-1:2005
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Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity



NOTE:
isolatewhen
and lock
off applies
equally
AlwaysElectrically
take precautions
working
on or near
liveto
escalators,
service lifts, lifting platforms and other
electrical equipment.
equipment
inout
addition
to conventional
lifts
Lock and tag
the supply
[or, if not possible,
remove the
fuses and take them with you] when power is not required
to perform the task.
Ensure that you verify that the disconnection has been
made
7
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity

 These
are thewhen
onesworking
that survived
Always take
precautions
near electrical
equipment.
8
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Always take precautions when working near electrical
equipment.
NOT a good Ellison switch with
Isolator
with out the supply [or, if not possible, remove the
 Lock
and
example
of tag
handle
handle drilled
and drilled and
isolation
fuses
and take
them with you] when power is not required
padlocked
padlocked
to perform the task.
Two engineers each apply
their own locks to secure
isolation by using multi-lock
hasp lock off devices
9
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Always take precautions when working near electrical
equipment.
Lock
and
tag
Verify
Confirm
Isolate
Lock
Off
test
isolated
and
device
Tagout
onthe supply [or remove the fuses and take
themcircuit
with you] when power is not required to perform the
by confirming
separate
Out
task.
voltage
present
 Ensure that you verify that the disconnection has been
made
10
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Never assume the disconnection has been
successful – you need to check that the
disconnect is effective and secured
11
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Lock off and
Safe Working with Electricity
tag out to
secure the
equipment
after isolating
12
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
“The test lamp or voltage detector should be proved to be working on a
known live source, proprietary proving unit or built-in test feature before
and after use. All line, neutral and protective conductors of the circuit
should be tested and proved to be dead.”
The Electrical Safety Council Best Practice Guide 2
13
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Always take precautions when working near electrical
“The test lamp or voltage detector should be proved to be working on a
equipment.
known
source,
proprietary
unit orthe
built-in
testand
feature
before
Lock
andlive
tag
out the
supplyproving
[or remove
fuses
take
and after use. All line, neutral and
protective
conductors
of the circuit
NOTE:
The procedure
for proving
dead
them with you]
when
power
is proved
notberequired
to perform
should
bytouse
a proprietary
testthe
should
be tested
and
beof
dead.”
task.
lamp orBest
two-pole
voltage
detector
as
The Electrical Safety Council
Practice
Guide
2
recommended in HSE Guidance Note
GS38: Electrical test equipment for use
by electricians
14
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Consider other sources which could remain
live – see later slide
15
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Regulation 14 Work on or near live conductors
No person shall be engaged in any work activity on or so near any live
conductor (other than one suitably covered with insulating material so as
to prevent danger) that danger may arise unless (a) it is unreasonable in all the circumstances for it to be dead; and
(b) it is reasonable in all the circumstances for him to be at work on or
near it while it is live; and
(c) suitable precautions (including where necessary the provision of
suitable protective equipment) are taken to prevent injury.
Electricity at Work Regulations 1989
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Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity


When the equipment must remain energized, effective
insulation and safe electrical working practices must be
used e.g. insulating rubber gloves, eye protection,
insulating rubber mats on floor, insulating plastic shroud,
all before accessing live parts, electrically insulated tools to
minimise the risk of injury.
Avoid the chance of earthing yourself by removing or
covering jewellery.
17
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity

When the equipment must remain energized, effective
insulation and safe electrical working practices must be
used e.g. insulating rubber gloves, eye protection,
Precaution if equipment is
insulating
rubber
mats
on floor, insulating
plastic
shroud,
Fitaccidentally
an insulating
to
Verification
Use an insulating
of rubber
liveshroud
- use insulated
Wear insulating rubber gloves
protect
against
accidental
gloves
rubber no
mat (BS 921)
tools (BS
EN 60900)
and tools so that there
electrically
insulated
injury.
(BS EN is
60903)risk
untilof
isolation
contact
with
live in
terminals
and
maintain
them
good condition
wear
eye protection
protect
–Standard
says notto
more
than
against
18mmflash
exposed tip
is proven
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Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
Without an insulating shroud it
would be easy to make
accidental contact with the live
terminalsThe charred remains
Replacement leads
required
of an electricians
glasses after being
caught unprotected
in
Poorly insulated
tools
a flash – more than 18mm of
tip exposed. These
should be discarded
19
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
When the equipment must remain energised,
Removeeffective
or cover watches,
rings, necklaces
(And
insulation and safe electrical working practices
must
be
And earrings?)
used e.g. rubber gloves, rubber mats onbracelets?
floor, insulating
plastic curtain, electrically insulated tools.
 Avoid the chance of earthing yourself by removing or
covering jewellery.
20
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity



Give yourself as much room as possible and remember –
keep the area free of surplus materials.
There should be suitable light levels (200 lux) at point of
work
Replace all equipment covers on completion of work as
soon as possible.
21
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity

Even though the mains three phase isolator to the control
panel is switched off, other sources may remain live.
Signals
Transformers
Door detectors
Door
Transformers
Signals
Lighting
Alarms
detectors
Fans
Lighting
Alarms
Fans
Think
Are any
of isolation
other devices
during
connected
the wholetoprocess
the lighting
– not
just in the controller.circuit?
What about the rest of the
installation?
22
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity

Even after all power has been isolated there is also the
danger of electric shocks from sources of stored energy.
Charged capacitors
Charged
VF drives
capacitors
VF drives
23
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity

Even after all power has been isolated there is also the
danger of electric shocks from sources of stored energy.
Charged capacitors
VF drives
These should be marked, but what if they aren’t?
24
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Safe Working with Electricity
These
Discharge
should
these
be or
marked,
take precautions
but what ifagainst
they aren’t?
any stored
energy with a Safe System of Work before working on
them
25
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
The Charter also covers works close to or on
unguarded machinery
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Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Before starting work on machinery...



Display a sign at all landings – discourages interference
Switch off the electrical or hydraulic supply and post a sign
Lock off the switch or remove the valve lever, or use
another method to ensure that the supply cannot be
restored while work is going on
27
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Before starting work on machinery...

Display a sign at all landings – discourages interference
28
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Before starting work on machinery...
Display a sign at all landings – discourages interference
 Switch off the electrical or hydraulic supply and post a sign
…hydraulic oil
supply…
Switch off electrical supply
and/ or…
…and post a sign
29
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Before starting work on machinery...
Display a sign at all landings – discourages interference
Switch off the electrical or hydraulic supply and post a sign
Lock off the switch to ensure it
Remove hydraulic
…put it in a
 Lock off the switch or remove
thebe
valve
lever,
orwork
use
cannot
restored
while
control leversecure place
is going
another method to ensure that
theonsupply cannot be
and…
restored while work is going on
30
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Working on machinery


Guards must be kept in position unless you need to remove
them to carry out work
Machinery must not be operated with the guards removed
unless:
31
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Working on machinery
Guards must be kept in position unless you need to remove
them to carry out work
 Machinery must not be operated with the guards removed
it isunless:
not practicable
You have
toawork
safe system
on the equipment,
of work to do
diagnose
so
faults,
lubricate or adjust the equipment whilst stationary and with
the guards in position
AND

32
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Working on machinery


Inspect ropes only whilst they are stationary and wear
gloves to inspect them
Cleaning of rotating parts: ropes, chains, sheaves etc. must
be done with the power isolated. Restore the power only to
move the machinery to a new position and isolate again
33
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Working on machinery



After handwinding, remove separate winding wheel and
brake release
After completing the work re-fix the guards with the
correct number of bolts or screws
Before supply is restored check no-one will be harmed
34
Electrically isolate and lock off when power is not
required and when working close to unguarded
machinery
Supervision

HSE advise that supervision arrangements must be
appropriate and proportionate to the risk – work on or
near to live conductors, inexperienced staff etc…


Personnel under training need to be supervised
Auditing arrangements for peripatetic workers

Ideally a formal inspection when manager goes on site to review
and record evidence of safe working procedure.
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36
LEIA Safety Charter

Protect yourselves and others from falls and falling objects.

Use and verify Stop and other devices when accessing,
egressing and working on car tops and in lift and escalator
pits to ensure total control of the equipment.

Electrically isolate and lock off when power is not required
and when working close to unguarded machinery.
37
LEIA Safety Charter

Now being incorporated into the new edition of the LEIA
Site Safety Handbook.

We ask you to sign in this handbook, to commit to the three
elements of the Safety Charter
38
Thank You for attending
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