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
1995 Daegu gas explosions Department Store chain, where 31 holes of 75 millimeter width that were going through a grout curtain were accidentally drilled through a city gas pipeline and resulted in gas leakages into the subway construction site through a nearby sewer lead to the explosion due to an unknown fire at the site. The explosion created a 50-meter pillar of fire. The accident killed 101 people, including 42 students, and injured 202. The 400-meter-long private parking lot on the construction site collapsed, and 60 buildings and 152 cars were damaged and the damage reached 54 billion won. The damage caused by the