Rubenstein Candace D, DenHartog Emiel A, Deaton A Shawn, Bogerd Cornelis P, DeKant Saskia
a Textile Protection and Comfort Center , North Carolina State University , Raleigh , North Carolina.
b TNO Earth, Life and Social Sciences , Department of CBRN Protection , Rijswijk , The Netherlands.
J Occup Environ Hyg. 2017 Jun;14(6):448-455. doi: 10.1080/15459624.2017.1296230.
A major concern for responders to hazardous materials (HazMat) incidents is the heat strain that is caused by fully encapsulated impermeable chemical protective suits. In a research project, funded by the US Department of Defense, the thermal strain experienced when wearing these suits was studied. One particular area of interest was the fluid loss of responders during work in these suits as dehydration may be an additional health concern to the heat strain. 17 City of Raleigh firemen and 24 students were tested at two different labs. Subjects between the ages of 25 and 51 were used for human subject trials in a protocol approved by the local ethical committee. Six different Level A HazMat suits were evaluated in three climates: moderate (24°C, 50% RH, 20°C WBGT), warm-wet (32°C, 60% RH, 30°C WBGT), and hot-dry (45°C, 20% RH, 37°C WBGT, 200 W/m radiant load) and at three walking speeds: 2.5 km/hr, 4 km/hr, and 5.5 km/hr. 4 km/hr was tested in all three climates and the other two walking speeds were tested in the moderate climate. Weight loss data was collected to determine fluid loss during these experiments. Working time ranged from as low as 20 min in the hot-dry condition to 60 min (the maximum) in the moderate climate, especially common at the lowest walking speed. The overall results from all experiments showed that fluid loss ranged from 0.2-2.2 L during these exposures, with the average fluid loss being 0.8 L, with 56% of the data between 0.5 L and 1 L of fluid loss. Further analysis showed that a suggestion of drinking 0.7 Liter per hour would safely hydrate over 50% of responders after one work-rest cycle. Applying this fluid volume over three work-rest cycles only put 11% of responders at risk of hypohydration vs. the 57% at risk with no fluid intake.
应对危险材料（HazMat）事故的人员面临的一个主要问题是，完全密封的不透水化学防护服会导致热应激。在美国国防部资助的一个研究项目中，对穿着这类防护服时所经历的热应激进行了研究。一个特别感兴趣的领域是，应急人员在穿着这些防护服工作期间的体液流失，因为脱水可能是热应激之外另一个需要关注的健康问题。17名罗利市消防员和24名学生在两个不同的实验室接受了测试。年龄在25岁至51岁之间的受试者按照当地伦理委员会批准的方案参与人体试验。对六种不同的A级危险材料防护服在三种气候条件下进行了评估：温和气候（24°C、50%相对湿度、20°C湿球黑球温度）、温暖潮湿气候（32°C、60%相对湿度、30°C湿球黑球温度）和炎热干燥气候（45°C、20%相对湿度、37°C湿球黑球温度、200瓦/平方米辐射负荷），并设置了三种步行速度：2.5公里/小时、4公里/小时和5.5公里/小时。在所有三种气候条件下都测试了4公里/小时的速度，另外两种步行速度在温和气候条件下进行了测试。收集体重减轻数据以确定这些实验期间的体液流失情况。工作时间从炎热干燥条件下低至20分钟到温和气候下60分钟（最长）不等，在最低步行速度下尤为常见。所有实验的总体结果表明，在这些暴露期间体液流失量在0.2 - 2.2升之间，平均体液流失量为0.8升，56%的数据显示体液流失量在0.5升至1升之间。进一步分析表明，建议每小时饮用0.7升水，在一个工作 - 休息周期后可使超过50%的应急人员安全补水。在三个工作 - 休息周期内摄入这个液体量，只有11%的应急人员有脱水风险，而不摄入液体时这一比例为57%。
