长时热辐射环境对消防头盔防护特性的影响

Influence of Long-term Thermal Radiation Environment on the Protective Characteristics of Fire Helmets

消防头盔的防护性能对于判断消防救援人员在热暴露环境中的安全十分重要。利用自主设计的长时热辐射测试平台,研究了消防头盔暴露于4级热辐射强度(2、5、7和10 kW/m^(2))下热学、力学、光学等性能参数的变化规律,测定了消防头盔各部位的内外温升、硬度和照度。结果表明:热暴露过程中,消防头盔的内外温升随热辐射强度的增大而增加,硬度、照度皆随热辐射强度的增大而衰减;当温度达到200℃时面罩起泡导致透光率下降,当热辐射强度为10 kW/m^(2)时面罩起泡面积过大造成其光学性能失效,且盔壳硬度过低造成其力学防护性能失效;消防头盔内顶部填充的缓冲层可有效吸收辐射热量,降低盔内温度,但不同位置热辐射对盔内温升速率无显著的影响。

The protective performance of fire helmets is very important to protect people's safety in heat ex-posure environment.Using self-designed thermal radiation setup,the thermal,mechanical and optical prop-erties of a fire helmet exposed to four levels of thermal radiation(2,5,7 and 10 kW/m^(2))were studied,and the internal and external temperature rise,hardness and illumination of each part of the helmet were meas-ured.The results show that the internal and external temperature rise of the fire helmet increases with the intensity of radiant heat flow,and the hardness and illumination decrease with the increase of radiant heat flow intensity;when the temperature reaches 200℃,the light transmittance decreases due to the foaming of the mask.When the foaming area is too large at 1o kW/m^(2),the hardness of helmet shell is too low,the optical performance declines,and the mechanical protection fails.The buffer layer filled on the top of the helmet can effectively absorb heat radiation and reduce the temperature in the helmet,but the heat source radiation at different positions has no significant effect on the temperature rise rate in the helmet.