Practical pre-cooling methods for occupational heat exposure

This study aimed to identify a pre-cooling method to reduce the physiological and perceptual strain, and the inflammatory response, experienced by individuals who wear personal protective equipment. Eleven males (age 20 +/- 2 years, weight 75.8 +/- 9.3 kg, height 177.1 +/- 5.0 cm) completed 15min pre-cooling (phase change vest [PCV], forearm cooling [ARM], ice slurry consumption [ICE], or a no cooling control [CON]) and 45min intermittent walk (4 km h(-1), 1% gradient) in 49.5 +/- 0.6 degrees C and 15.4 +/- 1.0% RH, whilst wearing firefighter ensemble. ICE reduced rectal temperature (T-re) before heat exposure compared to CON (Delta T-re: 0.24 +/- 0.09 degrees C, p < 0.001, d = 0.38) and during exercise compared to CON, ARM, and PCV (p = 0.026, eta(2)(p) = 0.145). Thermal sensation was reduced in ICE and ARM vs. CON (p = 0.018, eta(2)(p) = 0.150). Interleukin-6 was not affected by pre-cooling (p = 0.648, eta(2)(p) = 0.032). It is recommended that those wearing protective equipment consume 500 ml of ice slurry 15min prior to work to reduce physiological and perceptual strain.