Testing of Firefighting Foams to determine PFAS concentrations using TOP Assay

ALS is pleased to offer new analysis capabilities for firefighting foam. These foams contain Per- and polyfluoroalkyl Substances (PFAS), a group of chemicals that are found in aqueous film-forming foams (AFFF) used in fire suppression systems.

To comply with the latest regulations, it is necessary to analyze PFAS concentrations and assess stockpiles of existing foams. Additionally, it is important to verify that effective decontamination has been conducted when AFFF has been replaced with alternative fluorine-free foams (F3).

The main function of PFAS in AFFF products is to provide spreading and sealability properties. PFAS lower the surface tension of the foam, allowing it to spread rapidly on burning liquids, while also providing resistance to the diffusion of flammable vapors. The chemical stability of PFAS ensures the film persists in fire conditions. However, alternatives to C8 and C6 PFAS foams, such as F3 foams, have similar extinguishment performance and are increasingly being used as replacements.

Regulations Relating to PFAS in Foams EU 2020/784

In Europe and the UK, regulations require that if your site houses more than 50 litres of foam, the composition and volume must be reported to regulators if the PFOA content exceeds 25 parts per billion (ppb), or if PFOA-related substances, known as PFOA-precursors, exceed 1000 ppb. EU 2020/784 outlines a precise timeline for compliance and provides additional details.

EU 2021/1297

The EU has implemented additional regulations that mandate the analysis of perfluoroalkyl carboxylic acids containing nine to fourteen carbons (PFCAs C9-C14). These regulations, known as EU 2021/1297, require that the sum of C9-C14 PFCAs concentrations should not exceed 25 ppb or 260 ppb for the sum of C9-C14 PFCA-related substances.

Laboratory Analysis for Compliance

A comprehensive method of chemical analysis is required to assess the concentration of PFAS in fluorinated foams, verify that F3 foams are fluorine-free and determine whether effective decontamination of fire suppression systems has been achieved.

Total oxidisable precursor (TOP) assay can assess the presence of PFCAs and their precursors. In the environment, polyfluorinated PFAS (precursors) can slowly transform to create perfluoroalkyl acids (PFAAs). Many of the proprietary PFAS present within firefighting foams, that are not detected using conventional analysis, can be assessed indirectly using this tool. TOP Assay is now widely used by consultants and contractors who advise companies holding stockpiles of foams.

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Ensuring Effective Decontamination through Laboratory Analysis

During the replacement of F3 foams, PFAS can accumulate and create crystalline bilayers within pipework and storage infrastructure, resulting in contamination. To prevent this, it is essential to test F3 foams and detect any residual PFAS that may cause a rebound effect.

Swabbing tanks and pipework is an effective approach for measuring the amount of PFAS on the surface. Innovative swabbing methods can eliminate PFAS, and the TOP assay can be used to quantify the amount of polyfluorinated PFAS present in the sample.

For further information please contact:

PFAS Technical support Client Service