Protection of Feet in Cold Exposure

Abstract

Safety shoes worn in cold climates need to protect the wearer from work hazards while at the same time offering thermal comfort 1) . Ordinary street shoes can do a good job of keeping feet warm and comfortable within a wide temperature range of -5 to +25˚C under normal activities and with the body's own thermal reaction and heat redistribution. However, added moisture at +15 to +20˚C in combination with low activity may easily cause local cold discomfort. Total foot comfort is determined by the interaction of socks, soles and shoes. In order to choose correct footwear for cold weather it is necessary to define what is meant by cold in various user conditions. Such an approach may also eliminate some of the conflicting requirements from the footwear properties "wish list", including mobility, protection, insulation, waterproofing, vapour permeability, durability, weight, fit, etc. 2) .Based on this approach and footwear thermal properties, cold may be divided into the three ranges: cool (above +5˚C); around the freezing point of water (+5 to -10˚C); and cold (below -10˚C). For temperatures above +5˚C no specific consideration of footwear insulation is required. Most ordinary shoes and occupational footwear have a total insulation around and above 0.20 m 2˚C /W. This insulation should be enough to keep feet warm with medium-heavy activity at temperatures down to +5˚C. The use of somewhat thicker socks (e.g. sports socks in terry cloth) does affect the situation by maintaining warmth. For this range, footwear should be chosen to keep external moisture from entering and/or to allow internal moisture to leave the footwear.The temperature range of +5 to -10˚C is the most complicated due to changing weather conditions around the freezing point of water (0˚C). In this range, considerations for footwear choice should include both protection from external moisture and the need for greater insulation.At temperatures below -10˚C there is less external moisture available to penetrate the footwear, while moisture from sweating does not easily leave footwear due to low temperatures (condensation) in the outer layers of the footwear material package. In these conditions high footwear insulation and internal moisture management properties of the materials increase in importance. Abstract: The paper summarizes the research on cold protection of feet. There exist several conflicting requirements for the choice of the best suited footwear for cold exposure. These conflicts are related to various environmental factors, protection needs and user comfort issues. In order to reduce such conflicts and simplify the choice of proper footwear the paper suggests dividing the cold into specific ranges that are related to properties and state of water and its possibility to penetrate into, evaporate from or condensate in footwear. The thermo-physiological background and reactions in foot are briefly explained, and main problems and risks related to cold injuries, mechanical injuries and slipping discussed. Footwear thermal insulation is the m...

Kite Skier's Toe: An Unusual Case of Frostbite

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Verification of toe allowance of children's footwear and its categorisation

“…), but the requirement to maintain the proportionality of footwear in relation to the foot remains utterly crucial. Some types of fashionable footwear serve as accessories to garments, meaning the form of such footwear has importance but does not always fully support the physiological function of the foot (Goonetilleke 1999;Kuklane, 2009;Park, 2012;Staheli, 1991;Tailby, 1997).…”

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