飞行员配穿两种囊式抗荷服在不同环境温度和代谢水平时的热应激

THERMAL STRESS ON PILOT WEARING TWO BLADDER ANTI-G SUITS AT DIFFERENT ENVIRONMENTAL TEMPERATURES AND METABOLIC LEVELS

目的 探讨飞行员配穿囊式抗荷服在不同环境温度、不同代谢水平条件下的热应激 ,为评价囊式抗荷服的热负荷和制定相应的保障措施提供理论依据。方法 6名受试者分别配穿KH - 3抗荷服及配套装备和KH - 7抗荷服及配套装备 (以下分别简称为“KH - 3”和“KH -7”) ,以不同代谢水平暴露于 2 0℃、2 5℃和 35℃环境。每次试验 70min。测量了受试者配穿KH- 3和KH - 7时的卫生学参数、皮肤温度、直肠温度、心率等 ,并以综合热应激指数 (CIHS)评定了热应激防护等级。结果 KH - 3和KH - 7的各项卫生学参数 (clo值、im、im/IJ)均无显著差别。KH - 3对照Ⅲ组和KH - 7对照Ⅳ组 (2 5℃ ,1178～ 132 5kJ·h- 115min ,36 8kJ·h- 15 5min)的CIHS均未超过生理安全限的 6 0 % (分别为 3.5 4和 3.4 6 ,属轻度热应激 ) ;KH - 3高代谢组和KH- 7高代谢组 (2 0℃ ,84 6～ 10 30kJ·h- 170min)的CIHS在生理安全限的 6 0 %～ 95 %之间 (分别为4 .2 4和 4 .6 0 ,属中度热应激 ) ;KH - 3高温组和KH - 7高温组 (35℃ ,1178～ 132 5kJ·h- 115min ,36 8kJ·h- 15 5min)的CIHS却超过生理安全限的 95 % (分别为 7.31和 7.87,属重度热应激 )。结论 受试者配穿KH - 3与KH - 7时的各项卫生学参数、热应激等均无显著差别 ,但配穿后者比?

Objective To examine thermal stress on pilot wearing bladder anti-G suits at different environmental temperatures and metabolic levels,so as to provide theoretical basis for evaluating the thermal burden of bladder anti-G suits and making up safe measures. Methods Six subjects, alternately wearing KH-3 anti-G suit and KH-7 anti-G suit with complete sets of equipment at different metabolic levels, were exposed to 20 ℃,25 ℃ and 35 ℃ environments respectively for 70 min. The grades of heat stress were evaluated according to combined index of heat stress (CIHS).Results The parameters of hygienics, (clo value,im,im/It), between kH-3 and kH-7 were not significantly different. The CIHSs of KH-3 control group Ⅲ and KH-7 control group Ⅳ(25 ℃,1 178～1 325 kJ·h -1 15 min,368 kJ·h -1 55 min) did not exceed 60% of the physiological safe limit(CIHS=3.46,3.54 respectively,mild heat stress). The CIHSs of KH-3 and KH-7 high metabolic groups (20 ℃,846～1 030 kJ·h -1 70 min)was 60%～95% of the physiological safe limit(CIHS=4.21,4.60 respectively,moderate heat stress). The CIHSs of KH-3 and KH-7 high temperature groups(35 ℃,1 178～1 325 kJ·h -1 15 min,368 kJ·h -1 55 min)exceeded 95% of the physiological safe limit (CIHS=7.31,7.87 respectively,severe heat stress). Conclusion There were no significant differences in hygienic parameters and heat stress between the subjects wearing KH-3 and those wearing KH-7. But the latter subjects had higher skin temperature at lower limbs than the former; in certain environmental temperature range, the metabolic levels may result in more severe heat stress than the environmental temperature. It is worth paying attention.