Group C · gas group · IIB
What is the basis or note for Group C · gas group · IIB?
For Group C, category is gas group; iec / atex designation is IIB; basis or note is disputed: MESG 0.50–0.90 mm per exknowledge.com, Ethylene per ldpi-inc.com, recorded from its source on 2026-08-06.
C | IIB | Ethylene, ethyl ether | 0.50–0.90 mm
— exknowledge.com, retrieved 2026-08-06
- Category
- gas group our reading
- North American designation
- Group C verified
- IEC / ATEX designation
- IIB verified
- Basis or note
- MESG 0.50–0.90 mm sources disagree
Values marked our reading are our classification of what the source says — the source does not print them in those words. The quote below is the evidence for each one; judge it yourself.
Where each value comes from
The value above is stated away from the sentence quoted with the answer, so the passage that states it is shown here too.
North American designation
Group C | IIB | Ethylene, hydrogen sulphide
— all from exknowledge.com, retrieved 2026-08-06
Sources disagree
More than one authority states this, and they do not state the same thing. Both are reproduced with the source each came from — deciding between them is yours, not ours.
Basis or note
exknowledge.com says basis or note is MESG 0.50–0.90 mm, as of 2026-08-06.
C | IIB | Ethylene, ethyl ether | 0.50–0.90 mm
https://exknowledge.com/pages/nec-500-vs-atex-iec.html
ldpi-inc.com says basis or note is Ethylene, as of 2026-08-06.
Ethylene | C | 450 | 842 | 1,200 PSI | IIB
https://ldpi-inc.com/resources/classification-codes/class-1-locations/
Where the other sources' values come from
These values were taken from a passage elsewhere on the other source's page, not from the row quoted with it above.
Sources
- exknowledge.comhttps://exknowledge.com/pages/nec-500-vs-atex-iec.html
- exknowledge.comhttps://exknowledge.com/pages/gas-groups.html
- ldpi-inc.comhttps://ldpi-inc.com/resources/classification-codes/class-1-locations/
- euroswitch.comhttps://www.euroswitch.com/wp-content/uploads/euroswitch-hazardous-area-guide_V6.pdf