Fire Safety Engineering Alert – Reports of a fire incident involving an antifreeze sprinkler system with a high concentration of antifreeze solution led the National Fire Protection Association (NFPA) to conduct research and standards development activities.

NFPA has issued a revised Safety Alert regarding antifreeze in sprinkler systems.  The NFPA Standards Council has voted to issue four Tentative Interim Amendments (TIAs) for several NFPA standards including NFPA 13, 13D, 13R and 25.  Highlights of the new requirements are provided below.  NFPA documentation should be consulted for the fullest and most accurate accounting of these requirements.

New Systems

  • Must use factory premixed antifreeze solution
  • Glycerin is allowed up to 48%
  • Propylene glycol is allowed up to 38%
  • Other factory premixed antifreeze solutions that are listed for use in sprinkler systems
  • Must test antifreeze concentration annually

Existing Systems

  • Requirements for NFPA 13, 13D and 13R sprinklers systems are not identical
  • Generally, all existing systems must be initially tested for antifreeze type and concentration.
  • Glycerin up to 50% is allowed – if over – must be replaced with factory premixed 48% maximum
  • Propylene glycol up to 40% is allowed – if over – must be replaced with factory premixed 38% maximum.
  • Must test antifreeze concentration annually

By Jeff Harrington, CEO and Founder of Harrington Group, Inc.