Antifreeze usage in ESFR systems is allowed only if:

Antifreeze usage in ESFR systems is allowed only if:

• A. The antifreeze solution is ethylene glycol based
• B. The antifreeze solution is propylene glycol based
• C. The ESFR sprinkler is listed for use with the antifreeze solution
• D. The antifreeze solution is non-toxic

Answer: (C)

Antifreeze can be used in an ESFR system only if the sprinkler and all system components are specifically listed and approved for that antifreeze solution. The listing means the manufacturer has tested and certified that this exact antifreeze type and concentration won’t cause corrosion, deposits, or interference with the sprinkler’s operation or the system’s hydraulics. Simply choosing a glycol (ethylene or propylene) or claiming non-toxicity doesn’t guarantee compatibility or code approval; without the listing, the combination isn’t permitted.

Antifreeze can be used in an ESFR system only if the sprinkler and all system components are specifically listed and approved for that antifreeze solution. The listing means the manufacturer has tested and certified that this exact antifreeze type and concentration won’t cause corrosion, deposits, or interference with the sprinkler’s operation or the system’s hydraulics. Simply choosing a glycol (ethylene or propylene) or claiming non-toxicity doesn’t guarantee compatibility or code approval; without the listing, the combination isn’t permitted.