Sample testing programs help verify accuracy of formulated products
When it comes to the performance of FM Approved products, even slight deviations in formulation or construction can have consequences. For instance, many roofing membranes and foam insulations depend on certain additives to enhance fire resistance. If the percentage of fire retardant additive used varies for any reason, the fire performance of that product could be adversely impacted.
To help verify the chemical composition of products under consideration for certification or re-verify products as part of recurring surveillance audits, FM Approvals began conducting sample testing for existing FM Approved roofing membranes last year.
"This new level of product surveillance and monitoring should be reassuring to our customers and their customers," says Rich Ferron, FM Approvals vice president and manager of testing and certification. Product analysis is being carried out using advanced instruments, including Fourier-transform infrared spectroscopy (FTIR) and gas chromatography—mass spectrometry (GC-MS) (see Figures 1&2). "A key benefit for manufacturers is knowing that their competitors are being held to the same high standards."
Throughout the year, FM Approvals plans to roll out sampling programs to a growing list of product categories. Manufacturers impacted by sampling programs will be notified in advance.
Spectra and other analyses generated by sample testing will be used to evaluate and compare the chemical composition listed on batch sheets and other documentation. In addition, subsequent spectra and other analyses will be compared to previous sample data to determine formulation consistency.
For FM Approvals’ building materials group, product sampling has begun with roofing membranes, specifically those based on PVC, EPDM, KEE and TPO. "We collect samples during initial Approval programs and during surveillance audits," notes Phil Smith, FM Approvals vice president and manager of the building materials group. "We have completed the collection and analysis of the initial round of samples. Going forward, we will continue to collect and analyze samples of these products. The FTIR analysis is not how we judge the performance of a product; it is merely a way to determine if a material is the same as what we Approved."
According to Bob Lovell, FM Approvals operations vice president of auditing and quality assurance, "The only way to truly analyze a formulated product is by destructive analysis. Our customers have asked for us to implement this type of program for some time now and we’re excited to be able to provide this extra level of assurance."