Determining optimal clothing ensembles based on weather forecasts, with particular reference to outdoor winter military activities

Abstract

Military and civil defense personnel are often involved in complex activities in a variety of outdoor environments. The choice of appropriate clothing ensembles represents an important strategy to establish the success of a military mission. The main aim of this study was to compare the known clothing insulation of the garment ensembles worn by soldiers during two winter outdoor field trials (hike and guard duty) with the estimated optimal clothing thermal insulations recommended to maintain thermoneutrality, assessed by using two different biometeorological procedures. The overall aim was to assess the applicability of such biometeorological procedures to weather forecast systems, thereby developing a comprehensive biometeorological tool for military operational forecast purposes. Military trials were carried out during winter 2006 in Pokljuka (Slovenia) by Slovene Armed Forces personnel. Gastrointestinal temperature, heart rate and environmental parameters were measured with portable data acquisition systems. The thermal characteristics of the clothing ensembles worn by the soldiers, namely thermal resistance, were determined with a sweating thermal manikin. Results showed that the clothing ensemble worn by the military was appropriate during guard duty but generally inappropriate during the hike. A general under-estimation of the biometeorological forecast model in predicting the optimal clothing insulation value was observed and an additional post-processing calibration might further improve forecast accuracy. This study represents the first step in the development of a comprehensive personalized biometeorological forecast system aimed at improving recommendations regarding the optimal thermal insulation of military garment ensembles for winter activities.

Cardiovascular and thermal strain during 3–4 days of a metabolically demanding cold-weather military operation

“…Ainslie et al [ 42 ] observed T re values between 37.5 and 38 °C during 7.5 h of hill walking (9.5 kg external load carriage) when consuming 3000 kcal (about a 1700 kcal deficit). Similarly, Morabito et al [ 23 ] reported pill temperatures of ~38 °C after a 12-km winter movement in 3 h, about a 1 °C increase from rest. Sleeping deep body temperatures in the current study were similar to that observed during a 54-h physically intense, energy intake-restricted field training exercise in warmer ambient conditions [ 15 ], indicating that the insulation from clothing, sleeping bags, and shelter was adequate to protect against freezing injury during the two winter training exercises.…”

“…The degree of physiological strain is similar to hikes/military movements conducted over a 3–7.5 h timeline while carrying external masses of 9.5–31 kg [ 23 , 42 , 43 ]. In these “like” studies, HRs ranged from 110 to 135 beats min −1 (55–73% HR max ), similar to that observed in the present study.…”

“…Although these models have been available for over two decades, validation studies have been limited. Previous occupational studies using the IREQ to determine if adequate clothing was used by workers and soldiers during cold exposure has only been studied over the course of one working day [ 21 – 23 ]. Thermoregulatory models for use in cold conditions have primarily been validated and tested during cold-water immersion [ 24 , 25 ] and not during exercise in cold air.…”

Investigation of Human Cooling Concepts

“…Tako je optimalni oblačilni sistem, ki ga nosi uporabnik, tisti, ki zagotovi vzdrževanje temperature jedra človeškega telesa med 36 in 38 °C in temperature na površini kože med 20 in 35 °C [1]. Nadgradnja optimalnega oblačilnega sistema je zmogljiva programska oprema, s pomočjo katere se za različna delovna okolja lahko napove optimalna toplotna izolacija [2]. Takšen sistem in oprema sta za končnega uporabnika z vidika pregretja ali podhladitve izjemno pomembna.…”

Determinationof the Thermoregulatory Specifications for Thermal Manikins

“…The current focus in the development of manikins is the incorporation of numerical thermoregulatory models in the control systems regulating heat loss patterns in manikins (Wissler, 1985;Fiala 2001). Recent studies , Zavec Pavlinic et al 2011, Morabito et al 2011) have demonstrated that data regarding thermal and evaporative resistance obtained with sweating thermal manikins are useful for simulating human thermoregulatory responses to different environmental conditions, at different levels of work activity.…”