Kuklane Kalev, Ueno Satoru, Sawada Shin-Ichi, Holmér Ingvar
The Thermal Environment Laboratory, Division of Ergonomics and Aerosol Technology, Department of Design Sciences, Faculty of Engineering, Lund University, SE-22100 Lund, Sweden.
Ann Occup Hyg. 2009 Jan;53(1):63-8. doi: 10.1093/annhyg/men074. Epub 2008 Nov 14.
The present Comité Européen de Normalisation (CEN) and International Organization for Standardization (ISO) standards for safety, protective and occupational footwear EN ISO 20344-20347 classify footwear as cold protective by a pass/fail test where the limits are set for an allowed 10 degrees C temperature drop inside the footwear during 30 min at a temperature gradient of approximately 40 degrees C. It is questionable if a simple pass/fail test of this kind provides approved footwear that really protects the feet from cooling in exposures ranging from temperatures at +18 degrees C to as low as or even lower than -50 degrees C. This study selected for testing some professional footwear that could certainly not be considered as cold protective. Some footwear that could be used in cold was selected with as low insulation as the not cold-intended footwear. Also, a boot intended for cold was selected to be tested according to a modified standard at a temperature gradient of 70 degrees C. The footwear selection was based on insulation measurements with a thermal foot model. All footwear did pass the test. Although it is clear for the user that a sandal, a mesh shoe or a thin textile shoe is not cold protective, it is not as clear that an item of safety footwear, that has as low insulation as those mentioned above, could be classified as cold protective according to the present standards. Because of this, the user might have a deceptive feeling of safety and may be exposed to higher risks. As practically all professional footwear may pass this cold test, then the method/requirements should be radically changed or such a test should be removed from the standards.
目前欧洲标准化委员会（CEN）和国际标准化组织（ISO）关于安全、防护及职业鞋类的标准EN ISO 20344 - 20347通过一项合格/不合格测试将鞋类归类为防寒鞋类，该测试的限制条件是在大约40摄氏度的温度梯度下，30分钟内鞋内允许的温度下降10摄氏度。对于这样一种简单的合格/不合格测试能否提供经批准的、能在从+18摄氏度到低至甚至低于 - 50摄氏度的环境中真正保护脚部免受寒冷的鞋类，这是值得怀疑的。本研究挑选了一些肯定不能被视为防寒的专业鞋类进行测试。还挑选了一些可在寒冷环境中使用但隔热性能与非防寒鞋类一样低的鞋类。此外，还挑选了一款用于寒冷环境的靴子，按照修改后的标准在70摄氏度的温度梯度下进行测试。鞋类的选择基于使用热脚模型进行的隔热测量。所有鞋类都通过了测试。虽然对于使用者来说，凉鞋、网眼鞋或薄纺织鞋不具备防寒功能是显而易见的，但同样不那么明显的是，一款隔热性能与上述鞋类一样低的安全鞋类，根据现行标准却可被归类为防寒鞋类。因此，使用者可能会有一种虚假的安全感，从而面临更高的风险。由于几乎所有专业鞋类都可能通过这项防寒测试，那么该方法/要求应从根本上改变，或者应从标准中删除此类测试。
