Certain foam concentrates used to extinguish fires – especially AFFF – contain fluorosurfactants or PFAS. PFAS are harmful to the environment and health. That is why some are already banned in the EU and worldwide. Others will be or are subject to legislation the EU is currently preparing.
In this article, you will learn which foam concentrates are banned, what PFAS are, which limit values and transitional periods apply to PFOS, PFOA and other substances and also which foam concentrate will be banned.
What are PFAS?
- PFOS (perfluorooctane sulfonic acid) and
- PFOA (perfluorooctanoic acid).
All PFAS have in common that all hydrogen atoms on at least one carbon atom in the PFAS molecule have been replaced by fluorine atoms. Sometimes they are also called PFC (per- and polyfluorinated chemicals) or generally fluorine surfactants. They all refer to the same group of substances. If one speaks of PFAS in foam concentrates, one can also speak generally of fluorine-containing foam concentrates.
I wrote about the environmental and health hazards of PFAS in an article on AFFF.
Which PFAS does foam concentrate contain?
Of course, you want to know which substances your foam concentrate contains and whether it is affected by a ban. Unfortunately, this is where it gets a bit tricky. Why? Because almost every foam concentrate contains a whole range of fluorine surfactants as impurities, which can nevertheless exceed certain limit values. PFOA, for example, was never an active substance that was needed in foam. However, you can find it in many foam concentrates because it is a by-product of production. Unfortunately, the limit value for PFOA is so low that the ban affects many foam concentrates in extinguishing systems and firefighting appliances. The product name of the manufacturer only gives you the first clue. Over the years, the recipes have sometimes been changed without changing the product name. A change in the raw material supplier of the foam concentrate manufacturer could also have an impact. And finally, earlier changes in the foam concentrate in a tank can be an issue. In most cases, it is impossible to determine with certainty what was previously used. Many fire brigades were surprised to hear about the analysis results of their foams because PFAS from old stocks contaminated the new foam concentrate when the foam concentrate was exchanged without thorough cleaning.
The only safe way to determine whether your foam concentrate is affected by a ban is a laboratory analysis for PFAS.
Which PFAS are banned?
PFAS are not (so far) banned as a whole group. However, individual substances, such as PFOS or PFOA, are regulated. This makes the already complex subject even more difficult. But let’s do it step by step.
Basically, there are two mechanisms through which PFAS can be banned in the European Union. On the one hand, a substance can be regulated within the European Union via the so-called REACH regulation. A country or the EU Commission proposes a ban on a substance, and this ban is then discussed in a defined process. If the proposal is successful, the substance is included in the REACH regulation.
In addition, the EU is also a party to the Stockholm Convention on Persistent Organic Pollutants (in short: Stockholm Convention). Certain persistent pollutants are regulated in this internationally binding agreement. PFAS belong to the group of persistent organic pollutants (also known as POPs). Almost every country in the world is a party to the Stockholm Convention. Notable exceptions are the USA, Israel, and Malaysia. They have not ratified the treaty. But PFAS is also a big issue in the US, and state and federal governments are taking action to ban PFAS in firefighting foam. If a PFAS is included in the list of regulated substances as part of the Stockholm Convention, the EU implements the ban in an EU regulation. However, in the POP regulation and not in the REACH regulation.
A substance can be banned within the EU under the REACH regulation and later under the Stockholm Convention. In this case, the substance is usually taken out of the REACH regulation. It is then only regulated under the POP regulation. So far, this has always led to a tightening of the ban, which is what happened with PFOS and PFOA, for example.
To assess which fluorosurfactants are prohibited in foam concentrate, four aspects are important:
- The regulated substances
So far, PFOS, PFOA, PFHxS, PFHxA and C9-C14 PFCA are regulated. The latter are the perfluorocarboxylic acids with a chain length of 9 to 14 carbon atoms in the molecule. PFHxA (perfluorohexanoic acid) and PFHxS (perfluorohexanesulfonic acid) are other candidates that are expected to be regulated in the future. In addition, the European Union is planning a general ban on PFAS in foam concentrate and, separately, a ban on all PFAS in principle. It is important to know that not only are the individual substance prohibited but also the related substances or precursor compounds. These are all compounds that can naturally degrade to regulated PFAS. These precursor compounds make the assessment of a ban even more difficult. - The country where foam concentrate is regulated
While PFAS are the focus of regulators worldwide, the laws implementing the bans vary. For the countries of the European Union, this is still relatively manageable because the corresponding EU regulations are binding legal acts and apply directly, so they do not require a national law of their own. For other countries (e.g., the United Kingdom), national legislation needs to be checked. - Limit values
A certain limit applies to the use of PFAS. The ban only affects the foam concentrate when it exceeds that value. But be careful: The limit value applies to the sum of the regulated substance and all precursor compounds! Different limit values apply to some of the regulated PFAS, and I’ll go into the limits below. - Transition periods
If a regulation comes into force, it usually does not apply immediately, but there are transitional periods for certain cases. For foam concentrates, a distinction is made, e.g., in placing on the market, use, use for training, use in tests, etc. I will also go into this in detail below.
The ban on PFOS in foam concentrate
Perfluorooctanesulfonic acid (PFOS) was the first of the group to be banned in Europe. For a long time, PFOS was the most important active ingredient in AFFF and therefore was widespread. In 2006, the (now superseded) Directive 2006/122/EC came into force and banned PFOS in foam above a limit of 50 ppm (50mg/kg). However, stocks of foam concentrate containing PFOS held by fire brigades and in extinguishing systems were allowed to be used until 27th June 2011. Today, PFOS is listed in Annex I of EU Regulation 2019/1021, and the limit has been tightened to 10 ppm (10mg/kg). Foam concentrate containing PFOS has not been available for purchase for over 20 years and was only allowed to be used until 2011. Occasionally, however, users still have stocks of old foam concentrate.
The ban on PFOA in foam concentrate
Perfluorooctanoic acid (PFOA) was first regulated in the EU in 2017 under the REACH regulation. However, this only affected the manufacturers, and an exception was made for foam stocks. In 2019, however, PFOA was also banned internationally under the Stockholm Convention. In 2020, it was transferred to an EU regulation on PFOA, which replaced the old regulation in the EU. The new ban brought with it a tightening that now also affects the foam concentrate used by users.
What is the limit? The EU regulation restricts
- PFOA or one of its salts: 25ppb (0.025mg/kg)
- each individual PFOA precursor compound or combination of PFOA precursor compounds: 1ppm (1mg/kg)
Here you have to be careful with the units because:
1ppm (1mg/kg) = 1,000ppb (1,000µg/kg).
Compared to PFOS, the limit for PFOA is lower by a factor of 40. Which of these two limit values (25ppb or 1,000ppb) is to be used is again a bit tricky. That’s why I deal with it in an article about the PFAS analysis of foam concentrate. The lower limit of 25ppb applies in most cases.
However, transition periods apply to PFOA in foam concentrate
- Manufacturing and placing on the market (sale): Banned since 4th July 2020
- Storage by end users: Allowed until 4th July 2025 (but restrictions on use apply)
- Foam concentrate in the tank of fire engines and extinguishing systems:
- Allowed until 31st December 2022
- In addition, permitted until 4th July 2025, when the extinguishing water can be contained
- Banned for use after 4th July 2025
- Training: Banned since 4th July 2020
- Tests (to check the equipment): Permitted until 4th July 2025 if all releases can be contained and properly disposed of
It should be noted that the transition periods for PFOA only apply to firefighting foams used to fight class B fires (fires involving flammable liquids) or to cover spills of these fuels. It does not apply to fires involving solids (class A fires). Can you ensure that it is only applied for class B fires?
The ban on C9-C14 PFCA in foam concentrate
C9-C14 PFCA refers to the perfluorinated carboxylic acids with 9 to 14 carbon atoms in the chain. They were regulated – together with their salts and C9-C14-PFCA-related substances – in 2021 by the EU regulation 2021/1297. This ban has so far attracted little attention. These long-chain PFAS can be contained in the foam concentrate, just like PFOA. With regard to limit values and transitional regulations, the EU Commission has based it on the PFOA ban. However, there are still some deviations in detail. The following limit values apply:
- Sum of C9-C14-PFCA and their salts: 25ppb (0.025mg/kg)
- Sum of C9-C14 PFCA-related substances: 260ppb (0.26mg/kg)
There are also transitional regulations for the C9-C14 PFCA:
- Manufacturing and placing on the market (sale): Allowed until 25th February 2023
- Storage by end users: Allowed until 4th July 2025 (but restrictions on use apply)
- Foam concentrate in the tank of fire engines and extinguishing systems:
- Allowed until 31st December 2022
- In addition, permitted until 4th July 2025, when the extinguishing water can be collected
- Discontinued use after 4th July 2025
- Training: Banned since 25th August 2021
- Tests (to check the equipment): Permitted until 4th July 2025 if all releases can be contained and properly disposed of
As for PFOA, the C9-C14 PFCA transition periods only apply to Class B fires.
The ban on PFHxS in foam concentrate
Perfluorohexanesulfonic acid (PFHxS) was regulated on May 30, 2023, under EU Delegated Regulation 2023/1608, following a decision made under the Stockholm Convention a year earlier. The regulation sets a limit of 100 µg/kg (100 ppb) for PFHxS, its salts, and related compounds in foam agents, slightly higher than the general limit of 25 µg/kg (25 ppb). The EU Commission plans to review this specific limit in 2026. PFHxS may be present in foam agents as impurities, typically in low amounts.
The ban on PFHxA in foam concentrate
Perfluorohexanoic acid (PFHxA) is crucial for foam concentrates, as its precursors form the basis of all current PFAS-based foams, such as AFFF. PFHxA and its precursors are found in all fluorinated foams. On September 19, 2024, the EU regulation 2024/2462 introduced a limit of 25 ppb for PFHxA and 1000 ppb for its precursors. The restriction applies to training, public firefighting, and civil aviation, with transitional periods until April 10, 2026, for public use and October 10, 2029, for civil aviation. Public fire brigades handling major hazard facilities according to the Seveso-Directive 2012/18 can continue AFFF use solely for that purpose.
Which foam concentrates contain PFAS?
There are three main types of foam concentrate that contain PFAS.
- AFFF (Aqueous Film Forming Foam)
AFFF is by far the most common type of fluorine-based foam, and AFFF is also often used as a synonym for all PFAS-based foam concentrates.
In this article about AFFF, you will find everything you need to know about it. - FFFP (Film Forming Fluoroprotein) foam
Like AFFF, the film-forming fluoroprotein foam (FFFP) forms a water film. But unlike AFFF, it is not based on a synthetic surfactant but on a protein foam. - FP (Fluoroprotein)
Fluoroprotein foam concentrates were actually the first fluorine-containing foam concentrates to be developed. They do not form a water film, but the fluorine components in this foam concentrate reduce the fuel pick-up and make it more heat resistant.
However, it is not possible to say in general which PFAS are contained in what concentration in a specific foam concentrate. The ingredients can vary, especially in the case of existing stocks of foam, e.g., in tanks of fire engines or extinguishing systems. Due to contamination, foam concentrates that should be fluorine-free can also contain PFAS. This sometimes happens if the tank was not properly cleaned when switching from AFFF to a fluorine-free foam concentrate.
A laboratory analysis is required to determine the PFAS content in a foam concentrate. When selecting the laboratory, one should ensure that there is sufficient expertise and experience in the analysis of PFAS in foam concentrate (because the analysis of foam concentrate is more difficult than, for example, an analysis of PFAS in drinking water) and that all relevant PFAS are detected.
Future bans of PFAS in foam concentrates
With the abovementioned regulations, only some of the 4700+ PFAS are banned. In their search for substitutes for the chemicals, manufacturers often substituted the banned substance with other PFAS that are not yet regulated. However, the entire group of perfluorinated and polyfluorinated alkyl compounds is considered to be of concern. In some cases, the substitute products were found to be as harmful.
There are currently two pending legislations that aim to regulate PFAS in the EU
- Long Chain Perfluorocarbon Acids (LC PFCA)
The long-chain perfluorocarboxylic acids are also to be regulated. But wait, aren’t they already? Yes, the C9-C14 PFCA are banned in the EU, as I described above. Now, at the suggestion of Canada, they are also to be regulated internationally via the Stockholm Convention. This could also affect us in the EU in the future, e.g., in the form of changed limit values or an obligation to report foam concentrates that contain long-chain PFCA. It will probably be a few more years before this regulation comes into force. http://www.pops.int/TheConvention/ThePOPs/ChemicalsProposedforListing/tabid/2510/Default.aspx - PFAS in foam concentrate
At the initiative of the European Chemicals Agency ECHA, the regulation of PFAS as a complete group in foam concentrates was proposed. The intention was to avoid regrettable substitution, i.e., that manufacturers react to the ban of a certain PFAS with the introduction of another substance from the PFAS group. The initiative is currently in preparation and is expected to come into force in 2024. The current proposal (it can still change) contains a limit value of 1ppm (i.e., 1000ppb). This is significantly higher than the limit value for PFOA, for example. However, as with PFOA, it also refers to the sum of all PFAS and not just a single substance. Various transitional periods are provided for foam concentrates. Again, these are subject to change, but at this time, the following is suggested:- Seveso sites: 10 years
Other industries: 5 years - Civil aviation: 5 years
- Military: 5 years
- Municipal fire brigades: 1.5 years
- Ready-to-use applications (fire extinguishers): 5 years
- Marine applications (ships, offshore): 3 years
- Training and testing: 1.5 years
- Export: 10 years
https://echa.europa.eu/de/registry-of-restriction-intentions/-/dislist/details/0b0236e1856e8ce6
- Seveso sites: 10 years
In addition to the already not-very-simple regulations, there will be a few more in the future. However, it seems certain that sooner or later, we will have to say goodbye to foam concentrates containing PFAS in Europe and worldwide.