Transitioning from Fluorinated Foam to Fluorine Free Firefighting Foams
This is a follow-up to our December 2022 article on the transition to fluorine free firefighting foams, Transitioning from Fluorinated Foam to Fluorine Free Firefighting Foams Follow-Up:...
This is a follow-up to our December 2022 article on the transition to fluorine free firefighting foams, Transitioning from Fluorinated Foam to Fluorine Free Firefighting Foams
Follow-Up: Advancements in Firefighting Foam Technology
Since the introduction of Aqueous Film Forming Foam (AFFF) over half a century ago, it has been a staple in combating ignitable liquid fires. However, due to growing environmental and health concerns associated with its fluorine content, AFFF is facing rapid phasing out globally. In response, manufacturers have been diligently developing alternatives to meet the stringent requirements of firefighting standards while eliminating fluorine.
Recent Developments
In response to evolving regulations and bans, the field of fluorine-free foams has advanced significantly, offering robust fire suppression capabilities without the environmental concerns associated with fluorinated foams. Among these advancements, several new formulations of synthetic fluorine-free foam (SFFF) have gained approvals, underscoring their reliability. Like the original protein-based fluorine-free foams, SFFF does not produce a film that isolates liquid fuel from air. Effective fire extinguishment with SFFF relies on good bubble development through specialized aerating nozzles. While limited fire test data exists on the performance of SFFF with many ignitable liquid fuels, a 2019 study by the National Fire Protection Association (NFPA) highlighted the need for different application densities when extinguishing non-polar and hydrocarbon fuels, indicating that higher application densities are necessary to achieve performance levels comparable to AFFF. Although further testing and developments are likely, there are currently nine SFFF products that have received FM Approval and three that meet stringent MIL-SPEC requirements.
Transition to SFFF
The adoption of synthetic fluorine-free foam (SFFF) requires careful consideration of several factors, including equipment compatibility, the disposal of existing AFFF stocks, and adherence to evolving state and federal regulations. When selecting an SFFF foam, it's essential to review the manufacturer's specifications for application and system requirements, as specific SFFF formulations are typically approved for use only with their designated system components. Transitioning from AFFF to SFFF often requires replacing the entire fire suppression system, not just changing the foam concentrate. Similarly, switching between different SFFF formulations will necessitate replacing various system components alongside the foam itself.
Additionally, selecting the appropriate foam involves analyzing the liquids to be protected. For instance, polar solvents are miscible with water and can compromise the foam blanket, necessitating the use of alcohol-resistant synthetic fluorine-free foam (AR-SFFF). AR-SFFF formulations contain polymers that create a barrier between the fuel surface and the foam blanket, thus protecting it from destruction by polar solvents. The FM Approval listings provide information on the fuel hazards for which each SFFF and AR-SFFF foam is approved. Furthermore, each foam concentrate approval listing specifies compatible system components and application rates that must be used in conjunction with it. Therefore, it is crucial to choose the right foam concentrate, as any change in the liquid being protected—from non-polar to polar—or a switch to a different foam concentrate may require a reevaluation and potential replacement of system components.
Specific guidance on SFFF concentrates can be found in the FM Approval listings, FM Data Sheet 4-12, as well as in manufacturer specifications. The current NFPA 11 standard acknowledges SFFF as an alternative but offers limited guidance on its application. At this stage, NFPA 11 recommends consulting manufacturer specifications alongside the latest research and testing conducted by various organizations.
Looking Ahead
As industries and institutions prepare for the inevitable phase-out of AFFF, the focus remains on effectively integrating fluorine-free foams into existing fire suppression strategies. The most recent advancement in fluorine-free foam technology, SFFF, is gaining traction and receiving approvals, demonstrating its potential as a reliable alternative. To ensure a seamless transition, continued collaboration among stakeholders, ongoing research into foam performance, and proactive adaptation to regulatory changes will be crucial.
Conclusion
In conclusion, while the shift from AFFF to fluorine-free foams presents challenges, it also represents an opportunity for innovation and sustainability in fire protection. By staying informed and proactive, stakeholders can navigate this transition successfully while ensuring the adequacy of their fire protection systems.
Sources
FM Data Sheet 4-12
NFPA 11
Qualified Products Database (QPD)
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