Gaithersburg, MD – Temperature and heat-flow conditions can damage facepiece lenses on standard firefighter breathing equipment, according to research from the National Institute of Standards and Technology.
Researchers conducted fire experiments on self-contained breathing apparatus facepieces in vacant townhouses in the Chicago area. In two scenarios, the lenses exhibited bubbling, loss of visual acuity, deformation and, in one case, a hole, according to a press release from NIST.
Lens failure puts firefighters at risk for toxic gas exposure, respiratory tract burns and asphyxiation, NIST said.
Researchers tested five models of SCBA facepieces, and found damage was tied to temperatures and heat fluxes beyond performance limits for the polycarbonate lens material, according to the study abstract.
Before being sold, SCBAs undergo certification testing that requires passing the National Fire Protection Association’s “heat and flame test,” the press release stated. The test is conducted at high temperatures, but researchers said it does not reflect the heat conditions firefighters might encounter.