2026 Sprinkler Fitter Pro Test Blast – Ignite Your Path to Success!

Antifreeze in standpipe piping is prohibited because standpipes are intended to deliver clean water for firefighting and must remain compatible with the building’s drainage, testing, and discharge expectations. Introducing antifreeze could contaminate the supply, create hazardous discharges, and interfere with the operation and inspection of valves, gauges, and heads. In addition, many antifreeze formulations (including ethylene glycol and other glycol blends) are toxic or unsuitable for fire protection systems, and code requirements restrict antifreeze to only certain listed, purpose-built systems—not standpipes. So the safe, code-compliant stance is that antifreeze solutions are never permitted in standpipe systems.