I’m confused about NFPA 14.
It is stated that for Class I:
- maximum allowed pressure - 175 psi (12.1 bar)
- minimum allowed pressure - 100 psi (6.9 bar)
It is stated that for Class II:
- maximum allowed pressure - 100 psi (6.9 bar)
- minimum allowed pressure - 65 psi (4.5 bar)
My question is about class III system. As you know Class III is combination of Class I and Class II.
So there is no any pressure value to apply class III to comply with class I and class II at the same time.
(If I choice 6 Bar it does not complies to Class I. If i choice 8 bar this time it will not complies to class II)
What is your recommendation?
You go with the requirements of a class 1.
Above is a snippet.