Flame arrestors.. what standard determines if they are required.. ?

Not sure if UL or NFPA 30, or could be API, not in petroluem we've always used FA when CCFP is less than 100 def F.

Dear, Norsok standard p-100 may be iteresting


Best Regards
Qalander(Chem)

Sorry for mis-typing also see
UK HSE site
hsg 176& hsg 158
Good info

Best Regards
Qalander(Chem)

IMHO, flame arrestors should be considered for tanks only when multipe vents are collected into a header say, for a flare system.

As stated by the API guideline, the inspection and maintenance issue can be quite significant.

Lots of good information at PROTEGO.... a German Mfr.

Dear MJCronin Hello/Good Morning,
Generally I will second you,

since many Improperly serviced/maintained Flame arrestors resulted in in-sufficient out breathing

while internal over pressurization initiated&got built up

to the levels of internal explosion(or implosion whichever term preferred as me not native English speaking person)

That consequently lead to ripping off the top roof/shell circumferential seam in varying lengths;as per severity of each incident.

Best Regards
Qalander(Chem)

There are several standards, but few codes (a standard being a recommended or best practice, and a code being mandatory or law). The only code I know of applies to US facilities that collect vapors from ships or barges (Coast Guard rule). Standards include ANSI (UL 525), API RP2210 and Publication 2028. The UK had a standard (EN12874) that has been adopted as an EU standard (same number, EN 12874) but refuted as inadequate or even dangerous, by a UK study.

FAs are often mis-applied, improperly maintained, and usually mis-undertood, and therefore they are not code requirements. It is certainly preferable to include one (properly specified, installed and maintained) if the vent feeds a header. If the vent is direct to the environment, they are also preferred, as they are intended to keep an external fire from entering the tank via the vent, but again, they must be properly spec'd, installed, and maintained. perhaps the worst thing about them, is they often give a false sense of safety and yet are not operated and maintained correctly.