Imamura R, Rissanen S, Kinnunen M, Rintamäki H
Oulu Regional Institute of Occupational Health, Finland.
Ergonomics. 1998 Oct;41(10):1421-32. doi: 10.1080/001401398186180.
Manual performance while wearing a whole body covering NBC garment was studied at -10 degrees C. Hands were protected by thin cotton gloves, which were covered with rubber gloves. The test subjects were exposed for 40 min in one of the four conditions: standing at -10 degrees C, standing for 10 min followed by walking (5 km/h) for 30 min on a treadmill, standing while holding a solid steel bar (see section 2.2), or standing at 20 degrees C. Six different manual tasks were performed after each 40-min exposure. All tests were also performed with bare hands at 20 degrees C. Moreover, the effect of contact cooling on skin temperatures and rewarming thereafter was examined by means of gripping a steel bar (-10 degrees C) during cold exposure. During exposure to -10 degrees C conditions finger skin temperature rapidly decreased to 10.7 +/- 2.2 degrees C (mean +/- SD). Improvement of body heat balance by exercise increased finger temperatures to 19.6 +/- 9.0 degrees C. Hand temperature remained at a higher level both during rest and exercise at -10 degrees C (20.1 +/- 1.7 and 20.6 +/- 6.1 degrees C, respectively). Cold exposure deteriorated manual performance and especially those functions that are related to finger dexterity. Finger skin temperature had high correlation with screwing, peg-board and magazine loading tests (r = -0.90, r = -0.77 and r = -0.72, respectively, p < 0.01) but no relation was found with hand grip strength (r = -0.03). Manual performance was impaired in every test both by gloves and cooling. Contact cooling decreased skin temperatures on the palm side of the hand and fingers around twice as effectively in normothermic subjects and 3.9-6.5 times more effectively in cooled subjects in comparison to cooling by cold air alone. Contact cooling had no significant effect on skin temperatures on the dorsal side of the fingers. The rewarming rate after the release of the steel bar was clearly higher in the dominant hand in comparison to the non-dominant hand. In conclusion, the present results show that the thermal insulation of rubber gloves was clearly insufficient, allowing unacceptably low finger temperatures during work in the cold. However, only those tasks requiring finger dexterity were clearly adversely affected. Heat production by physical exercise was able to increase finger skin temperature and to partly restore manual performance. Handling of cold tools is especially harmful for the palm side temperature of the non-dominant hand.
在-10摄氏度的环境下，研究了穿着全身式核生化防护服时的手动操作情况。双手由薄棉手套保护，外面再套上橡胶手套。测试对象在以下四种条件之一中暴露40分钟：站在-10摄氏度的环境中；先站10分钟，然后在跑步机上以5公里/小时的速度行走30分钟；手持实心钢棒站立（见2.2节）；或站在20摄氏度的环境中。每次40分钟的暴露后，进行六项不同的手动任务。所有测试也在20摄氏度下裸手进行。此外，通过在寒冷暴露期间握住钢棒（-10摄氏度）来研究接触冷却对皮肤温度及其后复温的影响。在暴露于-10摄氏度的条件下，手指皮肤温度迅速降至10.7±2.2摄氏度（平均值±标准差）。运动改善身体热平衡后，手指温度升至19.6±9.0摄氏度。在-10摄氏度下休息和运动时，手部温度均保持在较高水平（分别为20.1±1.7摄氏度和20.6±6.1摄氏度）。寒冷暴露会降低手动操作能力，尤其是那些与手指灵活性相关的功能。手指皮肤温度与拧螺丝、插板和装填弹匣测试高度相关（r分别为-0.90、-0.77和-0.72，p<0.01），但与握力无关（r=-0.03）。手套和冷却在每次测试中都会损害手动操作能力。与仅通过冷空气冷却相比，接触冷却使常温受试者手部掌侧和手指周围的皮肤温度降低的效果约为两倍，使冷却受试者降低的效果为3.9 - 6.5倍。接触冷却对手指背侧的皮肤温度没有显著影响。松开钢棒后，优势手的复温速度明显高于非优势手。总之，目前的结果表明，橡胶手套的隔热效果明显不足，在寒冷环境中工作时会使手指温度低至不可接受的程度。然而，只有那些需要手指灵活性的任务受到明显不利影响。体育锻炼产生的热量能够提高手指皮肤温度，并部分恢复手动操作能力。操作冷工具对非优势手的掌侧温度尤其有害。
