模擬日光輻射熱暴露形成之熱負荷與熱適應以及防曬乳液使用對因應生理熱調節之影響

中國醫藥大學機構典藏 China Medical University Repository, Taiwan > 公共衛生學院 > 職業安全與衛生學系暨碩士班 > 博碩士論文 > Item 310903500/50328

請使用永久網址來引用或連結此文件: http://ir.cmu.edu.tw/ir/handle/310903500/50328

題名:	模擬日光輻射熱暴露形成之熱負荷與熱適應以及防曬乳液使用對因應生理熱調節之影響 Thermal Loading and Subsequent Adaptation in Response to Simulated Solar Radiant Heat Exposure and Influences of Sunscreen Use on Thermoregulation
作者:	張詩吟;Shih-Yin Chang
貢獻者:	職業安全與衛生學系碩士班
關鍵詞:	日光輻射熱;生理熱負荷;生理熱調節;皮膚生理指標;主觀熱感知;防曬乳液;Solar radiant heat;metabolic heat load;thermoregulation;skin physiological indicator;subjective thermal sensation;sunscreens
日期:	2013-07-23
上傳時間:	2013-10-02 11:24:01 (UTC+8)
出版者:	中國醫藥大學
摘要:	日光輻射熱是戶外環境中影響生?熱負荷的重要氣候因子。面對全球氣候變遷，高氣溫氣候的頻繁出現對於人體熱負荷與生理熱調節形成日益嚴峻的挑戰。以上高熱環境的潛在危害在都市地區更為顯著—常用於調節室內熱環境的空調系統不可避免地在建築物與外氣環境交接處產生溫度驟變之熱過渡區，對頻繁進出者構成逾量熱壓力。此外為了防止過度日光輻射暴露可能引起的健康傷害，國人常仰賴個人防曬用品如防曬乳液進行自我防護。本研究的目的在透過使用雙人工微氣候實驗室模擬輻射熱、環境溫度、及非環境因子(防曬乳液使用與否及性別)之組合，觀察不同熱環境變異狀態，包含微氣候因子固定之恆溫狀態以及因輻射熱消失所發生溫度瞬變狀況下，人體主觀熱感知與生理熱負荷/熱調節之反應與平衡，以及其中輻射熱影響之方式。本研究觀察生理熱負荷與熱調節之指標包括體核心指標及皮膚外顯散熱指標。體核心指標包括代謝率及核心溫度；皮膚散熱指標則包括皮膚微血流變化量、皮膚濕度、經皮水分散失度、與皮膚溫度。主觀熱感知與舒適感則以美國冷凍空調技師協會第55號標準問卷為基礎所發展之中文問卷調查。以上調查包括探討熱適應期之長短、生理指標之反應?時程關係、劑量?反應關係以及上述關係中輻射熱與使用防曬乳液所扮演之角色。研究結果顯示：與因空氣溫度變化產生的熱壓力相較，輻射熱所造成之生理熱負荷以及所驅動之熱調節反應幅度較大、所需適應期較長。以上變化以未使用防曬乳液之男性在黑球溫度為32oC時最為明顯；此時代謝熱之調節可透過皮膚濕度與經皮水分散失度變化觀察。當進入因輻射熱消失產生的熱過渡區時，皮膚微血流變化與皮膚溫度回復熱平衡所需時間較長，說明輻射熱對生理熱調節可能存有遲滯效應。使用防曬乳液可降低日光輻射熱曝曬產生之主觀灼熱感；其提供之涼膚效果亦明顯舒緩輻射熱形成之生理熱負荷與所驅動之生理熱調節，並減緩熱過渡區中因溫度瞬變對生理回饋造成之衝擊。與男性相較，女性的舒適感顯著地受熱感知影響。以上資訊當有助於現有熱危害警示系統之修正與提升防曬用品使用之正確認知，確保國人在溽暑季節防範熱危害之發生。 Solar radiant heat is amongst the most significant meteorological factors affecting metabolic heat load when people remain outdoors. In recent years, the frequent appearance of high ambient temperature in association with global climate change presents an increasing challenge to the physiological capacity of heat load and to that of thermoregulation. Among the affected, those who live and/or work in the urban areas are of particular concern—the thermal transient developed between the entrance of an air-conditioned building and the ambient environment often increases the thermal stress imposed on human body when people enter/leave the building. To prevent injury from over-exposure to solar radiation, the sunscreens are commonly adopted as a strategy of self protection. This study aimed to, by means of a series of experiments conducted in dual microclimatic chambers simulating different combinations of solar radiation, environmental temperature, and non-climatic factors including the use of sunscreens and the sex, investigate the physiological/psychological responses of human body to and the balance with thermal stress when the body is confronted with a thermal environment of either a steady state or a transient state due to a drop in environmental temperature following loss of solar radiant heat. The physiological indicators selected in the study were those of body core and of skin physiology involved in the dissipation of metabolic heat. The core indicators consisted of metabolic rate and core temperature, while the dermal physiological indicators included skin capillary blood flow, skin moisture, transepidermal water loss, and skin temperature. The subjective thermal sensation and thermal comfort were also gauged, using a standardized questionnaire developed by the American Society of Heating, Refrigerating, and Air-conditioning Engineers Standard 55. The study findings were analyzed to interpret the progress of heat acclimation (thermal adaptation), the time course of physiological responses as driven by thermoregulatory requirement, the relationship of dose (thermal exposure) and response for each individual event of thermoregulation, and the roles of the radiant heat as well as of using sunscreens in the aforementioned relationships. As the results show, the metabolic heat load and thermoregulation occurring in response to radiant heat exposure was greater and required a longer period to acclimatize compared to those resulting from exposure to the air temperature. These physiological changes in feedback to thermal pressure were particularly pronounced for males, as manifested in the alteration of skin moisture and transepidermal water loss, when not using sunscreens and thermally challenged at a globe temperature of 32oC. Upon entering the thermal transient developing from the sudden loss of radiant heat, the skin capillary blood flow and skin temperature required a longer period to re-equilibrate with the ambient environment compared to the requirements observed when the transient arose entirely as a result of air temperature step, suggesting a potential residual effect of radiant heat in delaying the thermoregulation occurring in response to the transient thermal environment. Using sunscreens reduced the burning sensation on the skin following exposure to solar radiation. In addition, the cooling effect of sunscreens significantly alleviated the metabolic heat load and thermoregulation resulting from exposure to radiant heat and from exposure to the thermal transient developing from a disappearance of solar raidation. The thermal comfort of females was more associated with the thermal sensation compare to that of males. These findings provide insights on how the current indices of thermal stress may be improved and promote a better understanding on the effects of using sunscreens in hot-and-humid areas such as Taiwan, protecting people from being thermally stressed from being exposed to solar radiation, particularly in hot summer days.
顯示於類別:	[職業安全與衛生學系暨碩士班] 博碩士論文

文件中的檔案:

檔案	描述	大小	格式	瀏覽次數
index.html		0Kb	HTML	158	檢視/開啟
index.html		0Kb	HTML	10	檢視/開啟

在CMUR中所有的資料項目都受到原著作權保護.

TAIR相關文章

資料載入中.....