During the years when there were no listed antifreezes to protect fire sprinklers from freezing in severely cold weather, dry pipe systems were often chosen to fill the void after NPFA put into place new regulations requiring listed antifreezes for new systems. The most common applications affected by this included attics, unheated warehouses, commercial freezers, overhead canopies, loading docks and parking garages. Now that listed antifreezes are commercially available, however, it’s worth evaluating experiences from the field where dry system use increased in situations where it might not have been best suited. While these systems can be the right solution in some scenarios, they can have significant drawbacks in others.
Many are not aware that the National Fire Protection Association (NFPA) fire sprinkler standards require new antifreeze systems to use an agency-listed antifreeze. And these same standards require that existing systems use an agency-listed antifreeze by September 30, 2022. In fact, when safety concerns led to these NFPA updates, no listed product was available.