Class B Firefighting Foam

One potential source of PFAS is the use of certain formulations of firefighting foams, referred to as Class B foam. NHDES is working with local and state emergency response personnel to gain an understanding about the use and composition of the various types of firefighting foams that are used to save lives and prevent property losses. These products are important resources for emergency responders that will continue to be necessary to perform their duties safely and effectively. Many types of Class B foams, which are typically used on flammable liquid fires and spills, may contain PFASs – specifically perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) that can contaminate groundwater and make it unsafe to drink even if only very small quantities are released to the environment.

In June 2016, NHDES worked with the New Hampshire Fire Marshall’s Office to conduct a preliminary survey on the use of Class B foam by fire departments across the state. In NHDES’ efforts to work with emergency response agencies and municipalities to address and better understand the use and the environmental concerns associated with Class B foams, the Waste Management Division is collecting information on where they may have been used in the past and when they are used in the future.

NHDES is also offering a Class B Firefighting Foam Use survey seeking to further evaluate where follow-up actions may be warranted at historical foam discharge sites and a Stock of Class B Firefighting Foam For Disposal survey seeking to evaluate the feasibility of offering a program to collect eligible foam stock that municipalities would like to dispose of. Additionally, on October 2, 2017, NHDES issued a letter to fire departments recommending that they voluntarily test on-site drinking water supply wells for poly and perfluoroalkyl substances (PFAS).

Manufacturers are reportedly reformulating Class B foams and some existing formulations purport to not contain the regulated PFASs. There is a fair amount of uncertainty regarding past and current formulations of Class B foams and NHDES continues to investigate.