CAN/CSA-E79-0-95 (R1999) PDF (Not Available)

CAN/CSA-E79-0-95 (R1999) is a standard that specifies the general requirements for the construction, testing, and marking of electrical apparatus used in explosive gas atmospheres. It is applicable to situations where the explosion characteristics of the gas atmosphere are within a specific range of pressures (80 kPa to 110 kPa) and temperatures (-20°C to +60°C). Any atmospheric conditions outside of this range may require special consideration.

The standard recognizes that there are specific types of protection for electrical apparatus in explosive gas atmospheres, which are addressed in various parts of IEC Publication 79. These include flameproof enclosures, pressurized enclosures, sand-filled apparatus, oil-immersed apparatus, increased safety, and intrinsic safety. It is recommended that apparatus that does not comply with the requirements of IEC Publication 79 but is recognized as safe for use in explosive gas atmospheres by a national or other appropriate authority should be marked with the symbol "s." However, this apparatus should still be part of apparatus that complies with the requirements of IEC Publication 79.

The standard also states that devices whose electrical parameters do not exceed certain values (1.2 V, 0.1 A, 20 µJ, or 25 mW) as per the manufacturer's specifications do not need to be certified or marked according to IEC Publication 79. However, if these devices are connected to a device that contains a source or storage element of electrical energy that could cause the circuit to exceed these parameters, they will be subject to the requirements of the various parts of IEC Publication 79.