Journal of the Korean Society of Clothing and Textiles (한국의류학회지)

The Korean Society of Clothing and Textiles (한국의류학회)
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Physiological Responses of Wearing Safety Helmet with Cooling Pack in Hot Environment

머리 냉각시의 인체생리반응 - 안전모 착용을 중심으로 -

  • Choi, Jeong-Wha (Dept. of Clothing & Textiles, Seoul National University/Research Institute of Human Ecology of Seoul National University) ;
  • Park, Joon-Hee (Dept. of Clothing & Textiles, Seoul National University)
  • 최정화 (서울대학교 의류학과/서울대학교 생활과학연구소) ;
  • 박준희 (서울대학교 의류학과)
  • Published : 2007.06.30
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Abstract

Safety helmets are used widely in various industries by workers since they are legally required to wear them. However, thermal discomfort is one of the major complaints from helmet users. To relieve this problem, frozen gelled packs can be considered for use inside the helmets. In this paper, tests were performed on humans to evaluate the physiological strains of wearing safety helmets and to investigate the effects of using frozen gelled packs inside the helmets. Experiments were conducted in a climatic chamber of WBGT $33{\pm}1^{\circ}C$ under four differed experimental conditions: 1) not wearing a safety helmet(NH); 2) wearing a safety helmet with frozen gelled pack A(HA); 3) wearing a safety helmet with frozen gelled pack B(HB); and 4) wearing only a safety helmet(OH). The results were as follows. First, when comparing NH with OH, physiological responses such as $\bar{T}_{sk},\;T_r$, HR and sweat rate were significantly higher in OH and subjective sensations were reported as less hot and more comfortable than NH(p<.05). Second, in regard to the frozen gelled packs inserted inside the safety helmets, some physiological responses in HA were different from those in HB, according to the two different types of packs. HA was hotter, more uncomfortable and less exhausted than HB. However, result from both HA and HB were lower than those from OH in terms of temperature and humidity inside safety helmet, sweat rate, $T_r$ increase, heat storage(p<.05). When wearing safety helmets with frozen gelled packs, it was shown that heat strain can be alleviated. These results are expected to help millions of workers who complain that wearing safety helmets is uncomfortable and messy.

안전모는 다양한 산업현장에서 머리 보호를 위해 착용되는 보호구로 법적으로도 착용이 의무화되어있다. 그러나, 안전모 착용에 따른 불쾌감 및 생리적 부담은 작업자들이 착용을 꺼려하는 주된 원인이 된다. 본 연구에서는 이 문제를 해결하기 위한 하나의 방안으로 안전모에 냉매팩을 삽입하는 방법을 제안하였고, 동시에 냉매팩 삽입으로 인한 안전모의 무게 증가가 인체생리반응에 미치는 영향을 규명하고자 하였다. WBGT $33{\pm}1^{\circ}C$의 환경에서 인체착용평가 방법을 이용하여, 4가지 실험조건으로 안전모 착용시의 인체 생리반응을 조사하였고, 그 결과는 다음과 같다. 첫째, 안전모만 착용 시(OH)와 안전모 미착용시(NH)를 비교해 보면, 안전모 착용 시에 평균피부온, 직장온, 심박수, 발한량 등이 통계적으로 유의하게 높았고, 주관적인 감각에서도 더 덥고, 더 습하며, 불쾌하고 주관적으로도 힘들다고 느끼는 것으로 나타났다. 둘째, 냉매팩 삽입시의 경우(HA, HB), 냉매팩의 종류에 따라 여러 인체생리반응에 차이를 보였으나, 안전모만 착용한 경우(OH)와 비교 시 안전모내 기후, 발한량, 직장온 상승도, 열저장(heat storage) 등이 더 낮았다. 한서감과 쾌적감에서는 냉매팩 종류에 따라 다른 경향을 보였다. 본 결과를 통해 안전모 착용시의 생리적, 주관적 부담 정도를 객관적으로 파악할 수 있었으며, 안전모에 냉매팩을 삽입하는 방법을 서열 스트레스를 경감시키는 하나의 방법으로 제시할 수 있었다. 추후 연구에서는 냉매팩의 무게, 피복면적, 성분 등을 고려해야 할 것이며, 본 결과가 서열 환경에서 안전모를 착용하고 작업하는 여러 산업 근로자에게 도움이 되기를 기대한다.

Keywords

References

  1. Abeysekera, J. D. & Shahnavaz, H. (1990). Adaptaion to discomfort in personal protective devices: An example with safety helmets. Ergonomics, 33(2), 137-145 https://doi.org/10.1080/00140139008927105
  2. Brown, G. A. & Williams, G. M. (1982). The effect of head cooling on deep body temperature and thermal comfort in man. Aviation, Space, and Environmental Medicine, 53(6), 583-586
  3. Cohen, J. B., Allan, J. R., & Sowood, P. J. (1989). Effect of head or neck cooling used with a liquid-conditioned vest during simulated aircraft sorties. Aviation, Space, and Environmental Medicine, 60, 315-320
  4. Crawshaw, L. I., Nadel, E. R., Stolwijk, J. A. J., & Stamford, B. A. (1975). Effect of local on sweating rate and sold sensation. Pflgers Arch, 354,19-27 https://doi.org/10.1007/BF00584500
  5. Froese, G. & Burton, A. C. (1957). Heat losses from the human head. Journal of Applied Physiology, 10(2), 235-241 https://doi.org/10.1152/jappl.1957.10.2.235
  6. Gagge, A. P., Stolwijk, J. A. J., & Hardy, J. D. (1967). Comfort and thermal sensations and associated physiological responses at various ambient temperatures. Environmental Research, 1(1), 1-20 https://doi.org/10.1016/0013-9351(67)90002-3
  7. Gavhed, C. E. D. & Holmer, I. (1989). Thermoregulatory responses of firemen to exercise in the heat. European Journal of Applied Physiology, 59,115-122 https://doi.org/10.1007/BF02396588
  8. Hardy, J. D. & Dubois, E. F. (1938). Basal metabolism, radiation, convection and vaporization at temperatures of 22 to $35^{\circ}C$. The Journal of Nutrition, 15(5), 477-497 https://doi.org/10.1093/jn/15.5.477
  9. Hayashi, C. & Tokura, H. (1996). Effects of head cooling on sweat rate in exercising subjects wearing protective clothing and mask for pesticide. Applied Human Science, 15(4),149-154 https://doi.org/10.2114/jpa.15.149
  10. Holland, E. J., Laing, R. M., Lemmon, T. L., & Niven, B. E. (2002). Helmet design to facilitate thermoneutrality during forest harvesting, Ergonomics, 45(10), 699-716
  11. ISO 9920. (1995). Ergonomics of the thermal environment: Estimation of the thermal insulation and evaporative resistance of a clothing ensemble. ISO Geneva
  12. Jung, D. J. (1994). The difference of the sweat rate and skin temperature according to environments during submaximal exercise. J. Kor. Soc. Tan-Therm. Environ. Sys., 1(1), 49-54
  13. Katsuura, T., Tomioka, K., Harada, H., Iwanaga, K., & Kikuchi, Y. (1996). Effects of cooling portions of the head on human thermoregulatory response. Applied Human Science, 15(2), 67-74 https://doi.org/10.2114/jpa.15.67
  14. Kim, H. E. & Park, S. J. (2004). The effect of safety hat on thermal responses and working efficiency under a high temperature environment. Applied Human Science, 23(5), 149-153
  15. Kissen, A. T., Summers, W. C., & Buehring, W. J. (1976). Head and neck cooling by air, water, or air plus water in hyperthermia. Aviation, Space, and Environmental Medicine, 47(3), 265-271
  16. Lee, B. H. (1996). Safety Sanitation protective equipment. Seoul: DongHwa Technology Publishing Co.
  17. Liu, X. & Holmer, I. (1995). Evaporative heat transfer characteristics of industrial safety helmets. Applied Ergonomics, 26(2), 135-140 https://doi.org/10.1016/0003-6870(95)00010-A
  18. Liu, X. & Holmer, I. (1997). Evaluation of evaporative heat transfer characteristics of helmets. Applied Human Science, 16(3), 107-113 https://doi.org/10.2114/jpa.16.107
  19. McCaffrey, T. V., Geis, G. S., Chung, J. M., & Wurster, R. D. (1975). Effect of isolated head heating and cooling on sweating in man. Aviation, Space, and Environmental Medicine, 46(11), 1353-1357
  20. Nunneley, S. A. & Maldonado, R. J. (1983). Head and/or Torso cooling during simulated cockpit heat stress. Aviation, Space, and Environmental Medicine, 54(6), 495499
  21. Park, J. H. & Choi, J. W. (2006). Work clothes and working environment of workers at a construction site in summer. Proceedings of the Korean Society of Clothing and Textiles, 30, 106
  22. Park, S. B. (1994). Characteristics of super absorbent polymer and state of the art. Mokchae Konghak, 22(1), 91-112
  23. Proctor, T. D. (1982). A review of research relating to industrial helmet design. Journal of Occupational Accidents, 3, 259-272

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