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Fire Main Diameter (SOLAS II-2)

Minimum fire main internal diameter per SOLAS II-2 Reg 10: d = 25 + 1.68·√(L·(B+D)).

Fire safetySOLAS
Fire main ID (minimum)
193mm
Formula, assumptions, and limits

Cast from SOLAS II-2 Reg 10-2. Branch diameters follow the same shape but with a smaller coefficient: d = 25 + 2.16·√(c·(B+D)) where c is the branch length. Use commercial pipe sizes (DN) one step up from the calculated value.

Symbol legend

SymbolMeaningUnitSource
Rule length (≈ LBP)mclass certificate
Beammclass certificate
Moulded depthmclass certificate
Fire-main internal diametermmresult