basis behind 10meter fire zone.. rule of thumb or data

[jamesbanda]

Dear all,

I was asked this recently..

I know the 10 meter fire zone for requiring fire protection is based on pool fires..a new engineering ask me for the basis...
i assume this is Hydrocarbon fires and typically heats generated... but is there any orginal data...

a referance would be adequate..

 

[Guidoo]

Good question.

I do not have the answer, but would like to add that the exact height varies per standard. NFPA 15 (A 4-5.1) mentions a height of 30 or 40 feet (say 9 or 12 m) where water spray cooling is to be considered for destillation columns, API 521 (3.15.1.1) mentions a height of 25 feet (say 7.5 m) when calculating fire relief requirements for vessels, and Shell DEP mentions a height of the Fire Protection Zone of 9 m above grade.

None of these standards give a reference for these heights.