Geology Reference
In-Depth Information
NO HAZARD
RISK
RISK
LEVEL
MITIGATION MEASURES
RESIDUAL
RISK LEVEL
LCR
L CR
5
Tunnel
atmosphere and
ventilation
including
accumulation of
explosive and
noxious gases
Explosion
risk. Possible
accumulation
of explosive
and or
noxious gas.
Methane,
associated
with coal or
other sources
is a
3
5
15
1. Provision of adequate
fresh air from the portal to
the excavation face.
2. Provision of adequate and
suitable atmospheric
monitoring system.
3. Avoid the use of dry
shotcrete mix.
4. Use explosive appropriate
to tunnels prone to
144
re
flammable
gas, lighter
than air and
can give rise
to explosion.
In large
quantities it
canalsocause
asphyxiation.
Other gases
such as carbon
dioxide,
carbon
monoxide,
sulphur
dioxide and
hydrogen
ulphide are
noxious.
risk.
5. Standby generators to
power fans.
6
Mechanical
breakdown
Failure of key
item of plant.
3
3
9
1. Planned maintenance
strategy.
2. Maintain spare plant items.
3. Maintain stocks of spares.
313
7
Use of explosives
Premature
detonation or
uncontrolled
explosion.
2
5
10
1. Employ quali
ed staff.
2. Comply with safety
regulations.
3. Use proper storage and
transport facilities.
4. Use non-electric
detonators.
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