Sources of ignition

• Pages: 26-32

5. Sources of ignition

5.1.

General

5.1.1.

All reasonable practicable steps should be taken to

eliminate the known sources of ignition.1

5.1.2. Where a source of ignition may possibly be present,

as in the firing of shots, or where heavy falls of quartzitic or pyritic

rock may occur in wastes, or where there is a danger that the packs

of a coal-cutting machine may strike quartzitic or pyritic material

in an undercut, special care should always be taken to ensure that

the atmosphere at and in close proximity to it is, as far as possible,

not flammable.

5.2. Restrictions on use of light alloy equipment

5.2.1.

(1) Because a particularly dangerous form of incendive

friction may arise from contact between rusty steel and light alloys

of magnesium and aluminium, the use of equipment containing

such light alloys in parts of a mine where there is a firedamp

hazard should be prohibited.

(2) If for practical reasons the use of equipment containing

such light alloys becomes necessary, the design should include

1 The most important sources of ignitions fall into six main

classes—

(a) electrical apparatus—by sparking (switching or short circuit), and by

heating of outer surfaces;

(b) electrostatic spark discharge;

(c) hot surfaces or sparks caused by the impact or frictional rubbing of

pieces

of

metal

or rock;

(d) incendive products from the discharge of explosives;

(e) underground

fires

and heating; and

(f) use of open or naked lights, and of contraband (i.e. illegal smoking)

underground.

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