Introduction to Fire Safety Management

Introduction to Fire Safety Management
104
hazard. For example, changing the work pattern by 
undertaking the refurbishment of a main staircase in a 
busy offi ce building concourse could be undertaken out 
of normal working hours thereby reducing the numbers 
of people exposed to the work or who may be affected 
by the work (means of escape partially obstructed). In 
relation to the management of dangerous substances in 
the event of a fi re, a mitigating measure would be the 
reduction of the number of persons potentially exposed 
by undertaking the work in a remote or segregated area.
When considering a method of work it may be 
possible to apply a different technique to reduce the 
risks such as using a roller to apply a coating material 
rather that using a spray technique which may present 
an additional explosion risk due to the atomised spray 
and the presence of ignition sources.
Reduction may also be achieved by the reduction of 
exposure time to a hazard, such as would be the case 
when managing the exposure time of persons involved 
in the transportation, storage, use and disposal of 
chemicals such as solvents. The Workplace Exposure 
Limit (WEL) assigned to acetone, for example, is 500 ppm 
in an 8-hour period, thus reducing exposure to the 
prescribed limit ensures that persons are kept free from 
ill health arising from the hazardous chemical. Acetone 
is, however, a chemical with a low fl ashpoint so even 
a small amount could present a fi re and explosion 
risk and thus reducing the volume is also a fi re control 
measure.
The single biggest reduction measure in relation 
to dangerous substances is to reduce the quantity or 
amount of the substance transported, stored, handled, 
etc. to the absolute minimum. This could be achieved by 
establishing a ‘call-off’ system whereby minimum stock 
levels are supported by regular deliveries keeping the 
stock levels down to the absolute minimum.
6.3.4 Isolation
Isolating the hazard from people by enclosing the haz-
ard should also be considered when elimination, substi-
tution or reduction cannot be achieved. Isolation can be 
achieved, when handling fl ammable and reactive mater-
ials, by the provision of a glovebox enclosure to prevent 
ill-health effects from inhaling the vapours, in addition 
to preventing the fl ammable vapours fi nding an ignition 
source causing a fi re or explosion.
Isolation of electrical supplies throughout a building 
(service risers) can be achieved by ensuring that the 
risers are fi re resistant enclosures, thus should a fi re start 
the secondary hazard (such as the production of smoke) 
is contained within the enclosure and will not have an 
adverse effect upon those escaping.
It may also be possible to undertake hot work within 
an enclosure which is fi re retardant and/or fi re resistant, 
thus isolating the risk of fi re progressing outside the 
enclosure by containing it within.
6.3.5 Control
Control can be achieved in two separate ways, although 
like many of the controls discussed in this chapter they 
may well be used together in an overall control strategy.