The explosion-proof certification mark is typically composed of multiple letters and numbers, each part having a specific meaning.

Shenzhen ZhongNuo Inspection will explain the meanings of each part of this symbol one by one:

For example, the common explosion-proof certification mark "Ex db ib IIC T4 Gb" means:

Ex: Indicates that the equipment is an explosion-proof electrical device, suitable for environments prone to flammability and explosion.

(2) db ib: Refers to the explosion-proof protection type of the equipment, meaning both explosion-proof (db) and intrinsically safe (ib). Explosion-proof type means that when an explosion occurs inside the equipment, the flame and explosion products will not spread to the outside through the equipment's joint surfaces; intrinsically safe type means that under normal operation and specified fault conditions, the electrical sparks or thermal effects generated by the equipment cannot ignite flammable and explosive mixtures.

(3) IIC: Indicates that the equipment is suitable for environments with IIC class flammable and explosive gases, which include:

(4) T4: Refers to the temperature category, indicating that the highest surface temperature of the equipment does not exceed 135°C, ensuring that it will not ignite any surrounding flammable or explosive mixtures at this temperature.

(5) Gb: Refers to the equipment protection level, applicable to Zones 1 and 2. Zone 1 is where flammable and explosive gas mixtures may occur under normal conditions; Zone 2 is where such mixtures are unlikely to occur under normal conditions, but may occasionally appear for short periods during abnormal conditions.

"Let's look at an example: 'Ex db eb II C T6 Gb'"

Ex:防爆型电气设备, also represented.

(2) db: Explosion-proof type protection.

(3) eX: The protection type is increased safety. Increased safety refers to taking additional measures for equipment that does not produce arcs, sparks, or high temperatures under normal operating conditions, to enhance its level of safety.

(4) II C: Indicates that the equipment is suitable for IIC classification of flammable and explosive gas environments, with representative gases being H2 and C3H8.

(5) T6: The equipment's maximum surface temperature does not exceed 85°C for the T6 temperature group.

(6) Gb: Equipment Protection Level, applicable to Zones 1/2.

It should be noted that this is just a common example of a防爆 certification mark used in environments with flammable and explosive gases. For equipment used in underground coal mines or environments with combustible dust, the防爆 certification mark will vary.

If you need more information about explosion-proof certification and explosion-proof markings, it is recommended to consultShenzhen Zhongnuo Inspection Technology Co., Ltd.We will provide more professional answers.