Liquefied Petroleum Gases, regulations

C, except a liquid which when tested at 55°C in the manner described in Schedule 2 to the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations 1972 does not support combustion. 

Highly Flammable Liquids and Liquefied Petroleum Gases Regulations 1972... 

The standard tests for determining the combustion characteristics of a flammable liquid are described in Schedules 1 and 2 of the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations 1972V The properties of some flammable substances are given in Table 25.1. 

Mineral-insulated, metal-sheathed (MIMS) cable is suitable for use in most environments, but it is not so suitable for use where there may be vibration. In an old paint spray booth which predated the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations, a spider-frame-mounted, electrical extractor fan had been positioned at the mouth of the extract duct and connected by MIMS cable. The fan motor was totally enclosed and explosion-protected as the paints used were flammable. The maintenance was poor and paint accumulations were allowed to build up on the fan blades causing an imbalance and vibration. This led to embrittlement of the copper sheath of the cable, which cracked and broke. Then one of the conductors fractured and sparking occurred between the ends. Ignition of the spray started a fire in the paint accumulations on nearby surfaces and the factory was burnt down. 

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