Electrical equipment in hazardous areas the participation of operations, maintenance, safety, electrical and instrumentation professionals, the use of process diagrams and material flows, MSDS and any pertinent documents, information and knowledge to determine the hazards and their extent and the countermeasures to be employed. Area classification documentations are reviewed and updated to reflect process changes. Soon after the introduction of electric power into coal mines, it was discovered that lethal explosions could be initiated by electrical equipment such as lighting, signals, or motors. The hazard of fire damp or methane accumulation in mines was well known by the time electricity was introduced, along with the
2008 Guangxi chemical plant explosions the cause is unknown. Other explosions continued until 1 p.m. Fire spread over an area of nearly 108,000 square feet (10,000m²). The explosions caused the leak of toxic substances, including ammonia, formaldehyde, acetylene, sulfurated hydrogen and carbon monoxide. At least 20 people were killed and at least 60 were injured; six people remained missing following the explosions. Fearing further explosions and leaks, the government evacuated 11,500 residents. Xinhua quoted the provincial toxic substances emergency center director as saying that the explosions causes no serious air or water pollution. The director also said that dams had been erected to prevent discharge