Severe sparking , static

External fire. May be prompted by flammable gas or vapor liquid, solid, metal, wood, or waste material pyrophoric material and presence of ignition source such as sparks, static, friction, hot spots, welding, lightning, auto ignition, or furnace. Immediate consequence engulfment, thermal radiation, fire damage, smoke, domino effect (where one incident is the primary cause for several other incidents). 

Fires may be started by one or several of die following so-called "common fire hazards matches and cigarets, rubbish (spontaneous ignition), locomotive sparks, mechanical spartks, friction, open-flame devices, heating appliances, electric wiring and equipment, static electricity and lightning. The primary object of fire prevention and extinction is to avoid loss of life and personal... 

The presence of static can be detected by instruments that measure the voltage or field strength, or, more crudely, by a gas discharge lamp which will glow if held in the field, or by the use of a wide band radio receiver and listening for the craekling sounds produeed by the field. In severe cases the sparking can be heard and seen. 

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