Explosion proof telephone used in Hazardous place

Industrial telephone

Hazardous place: any place with potential explosion hazard

■ Explosive dangerous environment will inevitably be formed in the production fields of petroleum, chemical industry, coal, etc.:

1. In coal mines, two-thirds of the places are explosive and dangerous places;

2. About 60-80% of the oil extraction sites and refineries are explosive hazardous locations;

3. In the chemical industry, more than 80% of the production workshops are explosive hazardous locations.

The basic principle of explosion (explosive triangle principle)

1. Flammable substances;

2. Air (oxygen);

3. Ignition source (electric spark, hot surface).

■ Basic methods to prevent explosion

1. Avoid the formation of an explosive environment-the ideal method (difficult to achieve)

2. Eliminate and eliminate possible ignition sources-practical methods;

3. Restricting one or a few of the elements can achieve the prevention

Explosion requirements. Such as manufacturing explosive gas concentration monitoring, restriction points

Fuel source (main means).

According to the frequency and duration of the explosive mixture, the gas and vapor explosion hazard environment is divided into zone 0, zone 1 and zone 2.

1. Zone 0 (Class 0 hazardous area) 　 refers to the area where explosive gas, vapor or mist occurs continuously or for a long time or frequently for a short period of time during normal operation.

2. Zone 1 (Class 1 hazardous area) "refers to an area where explosive gas, vapor or mist may appear (expected to appear periodically or accidentally) during normal operation.

3. Zone 2 (Class 2 hazardous area) 　 refers to the area where explosive gas, vapor or mist appears occasionally for a short time even if it does not appear during normal operation.