Classification of Hazardous Areas

[CLM]

Can some-one please tell me what the radius is from a possible leak that denotes the different zones in IIC areas (IEC). I only have NFPA standards at hand.

 

[Shortstub]

CLM,

IEC Group IIC covers Hydrogen. The comparable NFPA (NEC) Hazardous Location is Class I, Group B. Please note that they are not equal regarding the order of severity of exposion. I also believe, that test methods are different.

It is my understanding that IEC has more severe requirements!

 

[CLM]

Thank you Shortstub.
I know from NFPA that the area enclosing a potential leak has a 15 ft (4.57m) radius for Div. 2 and 5 ft for Div.1 (in open - ventilated gaseous) areas and that other rules apply for varying circumstances. Do you know what the IEC radii for Zones 0, 1 and 2?

 

[Shortstub]

Sorry, I don't!

 

[Aissa1972]

Hi-all :
if some-one can help me for the same question (determination of radius from a possible leak ) but with zones in IIA areas (IEC).
Conditions are in open areas for zone0, zone1 and zone2.
thanks for your quick reply.

 

[richanton]

Well, its a little late, but NFPA-497 has lots of figures showing different recommended scenarios for the USA requirements.