Temperature of the inhaled gaseous medium in fires is an important parameter of personal respiratory and eye protection equipment, however, the national standards do not regulate the temperature inside their front part. The main criterion considered during testing is the ability of the device to protect the user from toxic combustion products.
According to the requirements of national standards, the tests are aimed at assessing the resistance of one unit of the product to one of the types of temperature effects (heat flow, open flame) within the framework of one conducted test. At the same time, the temperature inside the front part and components of breathing apparatus is not recorded and monitored, as well as the effect of thermal fire factors on personal respiratory and vision protection equipment and their components.
Unlike the national standards, NFPA standard implies a comprehensive test to verify the protective properties of breathing apparatus with compressed air under the combined influence of various thermal factors.
In this situation, it is advisable to propose the following measures: temperature measurement at the most critical points of the internal space of the front part and housings of breathing apparatus with compressed oxygen and breathing apparatus with compressed air; comprehensive testing of the combined effect of thermal factors on all the structural elements of personal respiratory and vision protection equipment.
Thus, testing of personal protective equipment for respiratory and vision organs should be carried out under conditions of the combined exposure to thermal factors with variable values of the heat flux and exposure time, as well as considering the time of the protective action of personal protective equipment. This will provide an opportunity to assess the protective properties of personal protective equipment for organs under all types of thermal exposure, and update regulatory documents aimed at standardization in the field of application of personal protective equipment for respiratory and vision organs.
2. Loginov V.I., Arkhireev K.E., Ignatova I.D., Nekrasov D.A. Prediction of Burn Injuries during Testing of Special Protective Clothing for Firefighters at the Thermomanequin Test Bench. Bezopasnost Truda v Promyshlennosti = Occupational Safety in Industry. 2021. № 10. pp. 21–26. (In Russ.). DOI: 10.24000/0409-2961-2021-10-21-26
3. Stoll A.M., Piergallini J.R., Chianta M.A. Thermal conduction effects in human-skin. Aviation Space and Environmental Medicine. 1979. Vol. 50. № 8. pp. 778–787.
4. NFPA 1981. Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emergency Services. Available at: https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=1981 (accessed: October 19, 2022).
5. GOST 12.4.293—2015 (EN 136:1998). Occupational safety standards system. Respiratory system protective devices. Masks. General specifications. Available at: https://docs.cntd.ru/document/1200121957 (accessed: October 19, 2022). (In Russ.).
6. EN 137:2006. Respiratory protective devices — Self-contained open-circuit compressed air breathing apparatus with full face mask — Requirements, testing, marking. Available at: https://standards.iteh.ai/catalog/standards/cen/c0fca2ba-410f-4f35-a827-4d71730a59f2/en-137-2006 (accessed: October 19, 2022).
7. GOST 12.4.249—2013 (EN 145:2000). Occupational safety standards system. Individual protective respiratory devices. Compressed oxygen or compressed oxygen-nitrogen type self-contained closed circuit breathing apparatus. General technical requirements. Test methods. Marking. Available at: https://docs.cntd.ru/document/1200108358 (accessed: October 19, 2022). (In Russ.).
8. Koshcheev V.S., Kuznets E.I. Physiology and hygiene of individual human protection at high temperatures. Moscow: Meditsina, 1986. 255 p. (In Russ.).
9. Hirschler M., Beyler C.L. Thermal Decomposition of Polymers. Available at: https://gbhint.tripod.com/papers_5_13_02/368_Beyler_Hirschler_SFPE_Handbook_3.pdf (accessed: October 19, 2022).
10. LeGrand D.G., Bendler J.T. Handbook of Polycarbonate Science and Technology. New York: Marcel Dekker, 2000. 359 p.
11. Weaver J.A., Stoll A.M. Mathematical Model of Skin Exposed to Thermal Radiation. Aerospace Medicine. 1969. Vol. 40. № 1. pp. 24–30.
12. Nekrasov A.K., Loginov V.I., Arkhireev K.E., Mikhaylov E.S. Mathematical modeling of complex non-stationary heat exchange in multilayered heat-shielding designs with air spaces. Pozharnaya bezopasnost = Fire Safety. 2016. № 2. pp. 37–42. (In Russ.).