Temperature, Gas Groups and Area Classification Flashcards
What gas group is Propane in?
2A
What gas group is Ethylene in?
2B
What gas group is Hydrogen in?
2C
What gas group is Acetylene in?
2C
T1?
450
T2?
300
T3?
200
T4?
135
T5?
100
T6?
85
What are the Gas Groups?
2A - Less easily ignited (Propane)
2B (Ethylene)
2C - More easily ignited (Hydrogen)
Zone 0 - EPL, BS Zone, Atex Cert
Explosive gas vapour is continuously present/present for long periods of time (1000 hr)
EPL - Ga/Da
BS Zone - 0/20
Atex Cert - 1G/1D
Zone 1 - EPL, BS Zone, Atex Cert
Explosive gas/vapour is likely to occur during normal operation ( 10 - 1000 hr)
EPL - Gb/Db
BS ZONE - 1/21
Atex Cert 2G/2D
Zone 2 - EPL, BS Zone, Atex Cert
Explosive atmosphere is unlikely to occur (0.1-10 hr)
EPL - Gc/Dc
BS Zone - 2/22
Atex Cert 3G/3D
What equipment level is Ga?
It has very high level of protection. Can be used in all zones
What equipment level is Gb?
Has a high level of protection. Can be used in zone 1 and 2
What equipment level is Gc?
Has enhanced level of protection. Only used in Zone 2
What is Area Classification
Hazardous areas are classified in zones based on the frequency of the appearance and the duration of an explosive gas atmosphere
What T Class’s can be used for Hexane if ignition temperature is 240 deg?
T3 to T6
How are EPLs determined?
Determined on the basis of risk, taking into account the consequences of an ignition
Unless marked otherwise (T amb) what temp classification are suitable for an ambient temp range?
-20 deg to 40 deg
