Details

Autor(en) / Beteiligte

• Cadarette, Bruce S.
• Cheuvront, Samuel N.
• Kolka, Margaret A.
• Stephenson, Lou A.
• Montain, Scott J.
• Sawka, Michael N.

Titel

Intermittent microclimate cooling during exercise-heat stress in US army chemical protective clothing

Ist Teil von

• Ergonomics, 2006-02, Vol.49 (2), p.209-219

Ort / Verlag

London: Taylor & Francis

Erscheinungsjahr

2006

Link zum Volltext

Quelle

Taylor & Francis

Beschreibungen/Notizen

• The effectiveness of intermittent, microclimate cooling for men who worked in US Army chemical protective clothing (modified mission-oriented protective posture level 3; MOPP 3) was examined. The hypothesis was that intermittent cooling on a 2 min on-off schedule using a liquid cooling garment (LCG) covering 72% of the body surface area would reduce heat strain comparably to constant cooling. Four male subjects completed three experiments at 30°C, 30% relative humidity wearing the LCG under the MOPP 3 during 80 min of treadmill walking at 224 ± 5 W · m −2 . Water temperature to the LCG was held constant at 21°C. The experiments were; 1) constant cooling (CC); 2) intermittent cooling at 2-min intervals (IC); 3) no cooling (NC). Core temperature increased (1.6 ± 0.2°C) in NC, which was greater than IC (0.5 ± 0.2°C) and CC (0.5 ± 0.3°C) ( p < 0.05). Mean skin temperature was higher during NC (36.1 ± 0.4°C) than IC (33.7 ± 0.6°C) and CC (32.6 ± 0.6°C) and mean skin temperature was higher during IC than CC ( p < 0.05). Mean heart rate during NC (139 ± 9 b · min −1 ) was greater than IC (110 ± 10 b · min −1 ) and CC (107 ± 9 b · min −1 ) ( p < 0.05). Cooling by conduction (K) during NC (94 ± 4 W · m −2 ) was lower than IC (142 ± 7 W · m −2 ) and CC (146 ± 4 W · m −2 ) ( p < 0.05). These findings suggest that IC provided a favourable skin to LCG gradient for heat dissipation by conduction and reduced heat strain comparable to CC during exercise-heat stress in chemical protective clothing.