IEC 60079 - 10 Extent of zone

[Gilf]

Hi,

Is there anyone familiar with IEC 60079?

I'm designing an aircraft maintenance hangar. Ok, so the hangar space will be zone 1 as per IEC 60079 as I have jet fuel in the building. However, is the only way to determine the extent of zone to do the tedious calculation in the standard? NEC is so much more clear on this. I am so confused as to if I have consider the whole space (up to ceiling) a hazard zone or if there is a way that I can draw a line. For example, as per the NEC I can end the hazardous zone at 450mm above ground level. But I have no idea how I can draw the line according to IEC.

Thanks for any help in advance!

 

[rbalex]

I'm sorry no one else has been able to help you. I haven't done a true IEC Zone system since around 1997 and I no longer have access to the IEC Standards.

You have however stumbled on one of the more esoteric differences between IEC Zones and NEC Zones/Divisions. That is, IEC Zone 1 is more often like NEC Division 2 than Division 1.

One of the things I appreciated about the IEC system was that it tended to be more analytical than the NEC system. I'm afraid you will need to do the "tedious calculations" unless your enforcement agency would permit you to use NEC Section 513.3 as your basis. Surprisingly, many will.