We are all exposed, but some are more exposed than others

ABSTRACT

This paper defines functional cold exposure zones that illustrate whether a person is at risk of developing physical performance loss or cold weather injuries. Individual variation in body characteristics, activity level, clothing and protective equipment all contribute to variation in the effective exposure. Nevertheless, with the right education, training, and cold-adapted behaviours the exposure differences might not necessarily lead to increased risk for cold injury. To support the preparation process for cold weather operations, this paper presents a biophysical analysis explaining how much cold exposure risk can vary between individuals in the same environment. The results suggest that smaller persons are prone to be underdressed for moderate activity levels and larger persons are prone to be overdressed. The consequences of these discrepancies place people at different risks for performance loss or cold weather injuries. Nonetheless, even if all are well-dressed at the whole-body level, variation in hand morphology is also expected to influence hand skin temperatures that can be maintained; with smaller hands being more prone to reach skin temperatures associated with dexterity loss or cold weather injuries. In conclusion, this work focusses on bringing cold science to the Arctic warrior, establishing that combating cold stress is not a one size fits all approach.

KEYWORDS:

• Individual variation
• cold weather operations
• thermoregulation
• modelling

Acknowledgments

This is an extended version of the paper presented at the NATO RSY-HFM-349 Symposium “Human Performance and Medical Treatment and Support During Cold Weather Operations”. Koen van der Sanden (TNO) is acknowledged for reviewing and strengthening the paper through discussions.

Disclosure statement

The authors report there are no competing interests to declare. The views, opinions and/or findings contained in this article are those of the authors (Karl Friedl, John Castellani) and should not be construed as an official United States Department of the Army position, or decision, unless so designated by other official documentation. This article is approved for public release, and distribution is unlimited.

Additional information

Funding

BK was funded through Ministerie van Defensie V1917, V2316 and ITP CWO.