Kindly clarify Black steel pipe can be used in the foam concentrate line?
As per NFPA 16 2019 Clause 6.7.2.1
Foam concentrate pipe and valve shall me made of one of the following materials
1.Brass
2.Bronze
3.Stainless steel (304 or 316)
4.Other materials accordance with manufacturer certification and approved by AHJ
You could use black steel pipe in the foam concentrate line, but you must make sure that the pipe is completely filled with concentrate removing all air from the line. This must be done in order to avoid severe corrosion that could otherwise occur. However, it is better to use the material recommended in NFPA 11, so you will not need the approval of the AHJ.
- Brass - red brass, naval brass
- Stainless Steel - 304 and 316
- Plastic - Glas composite (green thread), PVC
- Carbon Steel A53-A106 - recommended for AFFF, AFFF AR, also for High-Expansion foam concentrates only when piping is flooded. (NOT RECOMMENDED FOR PROTEIN BASED AGENTS DUE TO CORROSIVENESS AND SOLIDS CONTENT OF PROTEIN AGENTS)
Notice: galvanized pipes and fittings must not be used with indiluted concentrate as corrosion will result
Thank you to all
Black steel pipe is the preferred material for foam concentrate pipelines.