THE BASIC OF EXPLOSION PROTECT

I. Cause of Explosion

An explosion is defined as a sudden reaction involving a rapid chemical oxidation of a flammable material with oxygen causing a simultaneous increment in pressure, energy and temperature. The explosion and fire can be occurred if the following three factor exist, in the right ratio, at the same time.

• Flammable material
• Oxygen in the air
• Source of ignition

The sample ignition sources that can cause explosion are:

• Hot surfaces of machine and equipment
• Flame and hot gas
• Arcing or sparking of electrical parts
• Mechanical and frictional spark
• Lightning strike
• Discharge of an accumulated electrostatic charge
• Electromagnetic wave

II . Hazardous Areas Classification

III. Typical ATEX/IECex Marking

–  Equipment marked IIB is suitable for application requiring Group IIA equipment. Similarly, equipment marked IIC is suitable for application requiring Group IIA or Group IIB equipment.

–  Equipment Class T2 is suitable for application requiring Class T1 equipment. Similarly, equipment Class T6 is suitable for application requiring Class T5, T4, T3, T2, or Class T1 equipment.

Example for the classification of gases, vapors and temperature classes:

IV. Degree of Protection Provided by Enclosures (IP Code)