Hose + Coupling World December 2021 Sample - Page 47


All PFAS Chemicals are Not the Same

There are currently a group of chemicals which have been placed in the spotlight and are receiving significant attention . Per-and polyfluoroalkyl substances ( PFAS ) are being discussed in the media and are constantly referenced as substances that will lead to the next industrial disaster . Some of the information depicted about these can at times be hyperbolic . The Fluid Sealing Association ( FSA ) is therefore actively trying to give concrete , fact based , knowledge about this subject to counter some of the more hysterical reactions to these issues . One of the major focuses of the FSA is on the chemical Polytetrafluoroethylene ( PTFE ).
By Ron Frisard , Global Training Manager , AW Chesterton / Gasketing Chairman of the Fluid Sealing Association
What are PFAS ? PFAS are a group of chemicals used to make fluoropolymer coatings and products that resist heat , oil , stains , grease , and water . There are over 4,700 known different chemicals that fit under the umbrella of PFAS . Fluoropolymer coatings are found in a variety of products , including clothing , furniture , adhesives , food packaging , and heat-resistant nonstick cooking surfaces . Many sealing products including valve packing , pump packing , gasketing , and O-rings in mechanical seals also contain Fluoropolymer .
In order to highlight the vast range of chemicals , one can think of each compound as a different type of cat that exists in the world . Imagine 4,700 felines frolicking in a field . A lion and a tiger tussle at one end . A pair of kittens unravel yarn at the other . And in between , there are 4,696 leopards , pumas , jaguars , lynx , panthers , and house cats . Now imagine 4,700 PFAS per- and polyfluoroalkyl substances — polymers as well as non-polymers , spread across that same field . Some are large molecules . Others are small . Some are bioavailable , some are not . All are PFAS , and just as the felines , come in all shapes , sizes , and ferocity .
PFAS Chemicals are Not all the Same All PFAS chemicals are not equal and should not be regulated as if they are . Each should be treated differently according to its application and toxicity . Umbrella legislation or regulation against all PFAS could end the use of non-harmful PTFE , a protector of people , the environment , and industrial equipment . According to the Organization of Economic Cooperation and Development ( OECD ), “ PFASs are a chemical class
with diverse molecular structures and physical , chemical , and biological properties , and it is highly recommended that such diversity be properly recognized and communicated in a clear , specific and descriptive manner . The term ‘ PFAS ’ is a broad , general , non-specific term , which does not inform whether a compound is harmful or not , but only communicates that the compounds under this term share the same trait for having a fully fluorinated methyl or methylene carbon moiety .”
Why is PTFE Important ? PTFE polymers in their finished form are corrosion resistant , save energy , increase safety , and allow easy movement of machine elements . These products are used in infrastructure , aerospace , military , power generation , chemical processing , food , and pharmaceutical industries . Fluid sealing products , including those with PTFE serve an essential role . They improve energy savings , reduce emissions , worker safety , and equipment reliability . The FSA promotes a targeted approach to regulating hazardous chemicals . It generally opposes regulatory overreach , and a one size fits all approach to PFAS chemicals , ( would include safe PTFE and other fluoropolymers ) as it may lead to unintended consequences for the climate , economy , and safety .
PTFE materials are " generally regarded as safe " by the FDA and are approved for implantation and various medical devices per USP Class VI designation . In sealing products , PTFE prevents leakage from industrial equipment . Leaks from these assets contribute to greenhouse gas emissions in some applications and create significant safety hazards in others . Seals that utilize PTFE polymers reduce leakage rates
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