GB 25286.1-2010

This part specifies the basic methods and requirements for the design, structure, testing, and marking of non-electrical equipment used in potentially explosive environments involving gases, vapors, mists, and air, as well as dust and air.
This part applies to environments with an atmospheric pressure of 0.08 MPa to 0.11 MPa and an ambient temperature of -20 °C to +60 °C. Such environmental conditions may also occur inside the equipment. This is because fluctuations in the internal working pressure and/or temperature of the equipment can lead to natural ventilation, allowing external atmospheric air to be drawn into the equipment interior.
For equipment not belonging to the aforementioned usage environments, its design, structure, testing, and marking may also refer to this part. However, in this case, the equipment's ignition hazard assessment, provided ignition protection, additional testing (if necessary), manufacturer's technical documents, and user manuals should clearly confirm and explain that the equipment is suitable for these conditions.
Note 1: This part does not include additional markings for equipment beyond its effective use range, such as oxygen-enriched environments.
This part specifies the design and structure of all classes of equipment for use in explosive environments: Class I, Class II, and Class III.
This part may be supplemented by the following specialized flameproof type standards.
Note 2: These standards are:
Explosive Environments - Non-Electrical Equipment Part 2: Flame-Restricted Enclosures (fr);
Explosive Environments - Non-Electrical Equipment Part 3: Flameproof Enclosures (d);
Explosive Environments - Non-Electrical Equipment Part 5: Constructional Safety (c);
Explosive Environments - Non-Electrical Equipment Part 6: Ignition Source Control (b);
Explosive Environments - Non-Electrical Equipment Part 7: Positive Pressure (p);
Explosive Environments - Non-Electrica