When your pump is intended to be used in an Atex classified explosive atmosphere, the Japy nameplate of the pump contains the following additional information:

The symbol that indicated that your pump complies with Atex directive 94/9/CE

The group number in Roman numerals, namely I or II :
where I is for mining industries. II is for other industries.

The category of your pump: 1, 2 or 3
1: for the sites at which an explosive atmosphere is present for more than 1000h per year.
2: for the sites at which an explosive atmosphere is present for between 10 and 1000h per year.
3: for the sites at which an explosive atmosphere is present for less than 10h per year.

The letter G and/or D
This indicates that your pump is designed for use in an explosive atmosphere due to the presence of gas or inflammable vapour (G for gas), or is recommended when the explosive atmosphere is due to the presence of inflammable dust (D for dust). The double mark GD indicates that your pump can be used in either 2 atmosphere.

The temperature class of your appliance: T1, T2, T3, T4, T5, or T6
The temperature class is the maximum surface temperature attained by the pump. It is given for an atmosphere at 40°C, but depends on the temperature of the fluid pumped. The relationship between the temperature class and the temperature of the fluid pumped is indicated after the temperature class.

T1:450°C; T2: 300°C; T3:200°C; T4: 135°C; T5:100°C; T6:85°C

Marking example: II 2 G T4 (Tf<120°C) Tf is the maximum temperature of the fluid.