Spark and shock hazards

While electrostatic precipitators have relatively high collection efficiencies (99-100%) over a wide range of particle sizes ( 0.05-5 /im), there are a number of disadvantages. These include the lack of size information, particle reentrainment due to sparking, and practical problems such as high cost and shock hazards. As a result, they have not been widely used in ambient air studies. 

Noncode wiring and switches present an explosion hazard (electrical spark) and a shock hazard (especially if there is water on the floor). 

Gas fumes, radiation, and electric shock are very real hazards that you face on the job as an arc welder. Think about it — a welding arc is hot enough to melt steel, and the light it emits is literally blinding. It generates toxic fumes that are composed of microscopic particles of molten metal. Sparks and molten slag thrown by the arc can fly up to 35 feet and can cause fires and explosions. 

FIGURE 5.3.5.2 Outlet in Chemical Hood. A strip outlet in a chemical hood represents a fire hazard since the outlets and switch are not spark-proof and flammable chemicals are often used in hoods. The dangUng cords might also present a trip hazard. A liquid spiU could also present a shock hazard. (From Journal of Chemical Health and Safety 7(5) 6 (2000). Used with permission. Copyright 2000 Division of Chemical Safety and Health of the American Chemical Society.)... 

Although thermal decomposition (and runaway) is often identified with the inherent reactivities of the chemicals involved, it must be emphasized that hazards can arise from induced reactions as discussed in Chapter 2. These induced reactions may be initiated by heat, contamination, or mechanical means (e.g., shock, friction, electrostatic spark). 

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