The classification of explosion-proof levels for electrical equipment is based on the type of equipment used, the temperature group of explosive gases, and the explosion-proof type of the electrical equipment. Electrical equipment
Explosive-proof electrical equipment is divided into two categories: Category I includes electrical equipment used in coal mine underground; Category II encompasses electrical equipment used in locations other than mines, differentiated based on the Minimum Experimental Safe Gap (MESG) or Minimum Ignition Current (MICR). Category II electrical equipment further breaks down into three subclasses: IIA, IIB, and IIC.
The above four categories are primarily divided based on the potential spark quantities that may ignite under different working conditions. China, as well as most countries and regions in Europe and around the world, categorizes explosive gases into these four hazard levels. The specific distinctions are as follows in the table below. Furthermore, according to the ignition temperature differences of explosive gases, the groups are further divided into T1, T2, T3, T4, T5, and T6. The ignition temperature is represented by t (°C).