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1

Effectiveness of a cooling jacket with reference to physiological responses in iron foundry workers

Shirish A., Kapadia V., Kumar S., Kumar S., Mishra S., Singh G.

International Journal of Occupational Safety and Ergonomics

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2016

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Vol. 22, No. 4

487--493

EN

Personal cooling garments (PCGs) have gained increased attention in recent years due to heat stress and strain in the working environment. The present study was conducted in hot environments of an iron foundry to evaluate the efficacy of a battery-operated PCG. Twenty-four workers were exposed to climatic conditions of 35.89 ± 1.25 °C, 35% relative humidity during 90-min work with PCG and habitual clothing (HC). Mean weighted skin temperature was significantly lower by 4.84 ± 1.05 °C compared with HC 0.38 ± 1.02 °C (p < 0.05). A statistically significant difference was also observed for 0.492 ± 0.26 g mean sweat loss in the PCG group compared with 0.775 ± 0.42 g in the HC group (p < 0.05). Heart rate, and back and chest skin temperatures were comparatively more reduced in the PCG group compared with the HC group. PCG provides a practical and economical way of alleviating the physiological effects of heat stress when environmental control is not feasible.

2

Test of Firefighter’s Turnout Gear in Hot and Humid Air Exposure

Holmer I., Kuklane K., Gao C.

International Journal of Occupational Safety and Ergonomics

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2006

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Vol. 12, No. 3

297--305

EN

Five students of a rescue training school cycled at 50 W for 20 min at 20 oC before walking at 5 km/hr up to 30 min in a climatic chamber at 55 oC and 30% relative humidity. 4 different types of clothing ensembles differing in terms of thickness and thermal insulation value were tested on separate days. All subjects completed 28–30 min in light clothing, but quit after 20–27 min in 3 firefighter ensembles due to a rectal temperature of 39 oC or subjective fatigue. No difference in the evolution of mean skin or rectal temperature was seen for the 3 turnout ensembles. Sweat production amounted to about 1000 g in the turnout gears of which less than 20% evaporated. It was concluded that the small differences between the turnout gears in terms of design, thickness and insulation value had no effect on the resulting heat physiological strain for the given experimental conditions.

3

Physiological Evaluation of Chemical Protective Suit Systems (CPSS) in Hot Conditions

Ilmarinen R., Lindholm H., Koivistoinen K., Helisten P.

International Journal of Occupational Safety and Ergonomics

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2004

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Vol. 10, No. 3

215--226

EN

This job-related experiment investigated physiological strain in subjects wearing impermeable chemical protective suit systems (CPSSs) weighing about 28 kg. Two types of CPSSs were studied: the self-contained breathing apparatus was carried either inside or outside the suit. Eight healthy and physically fit male firefighter instructors aged 32 to 45 years volunteered for the study. The test drill, performed at a dry, windless ta of 40 °C, was divided into 2 consecutive work sessions of 14.5 min (a 20-min rest between) including typical operational work tasks. Considerable thermal and maximal cardiovascular strain and intense subjective discomfort measured in the firefighters emphasize the need to limit working time in hot conditions to only 10-12 min while wearing CPSSs. The present results indicate that the exceptionally heavy physical load and psychological stress during operations in chemical emergencies must be considered in the assessment of the cardiovascular capacity of ageing firefighters using CPSSs.

4

Ergonomics in Practice: Physical Workload and Heat Stress in Thailand

Yoopat P., Toicharoen P., Glinsukon T., Vanwonterghem K., Louhevaara V.

International Journal of Occupational Safety and Ergonomics

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2002

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Vol. 8, No. 1

83--93

EN

This study consists of assessments of the thermal environment and physiological strain in tasks associated with airport, construction, and metal jobs. The number of male and female participants was 108. Environmental heat stress was evaluated with the WBGT index. Physiological strain was evaluated by the relative cardiovascular load (%CVL) based on the measurements of heart rate. Also the increase of body temperature, weight loss, and perceived discomfort were determinated. At work sites the assessments lasted for 2 to 4 hrs for each participant. The mean physiological strain exceeded the level of 30%CVL. Severe peaks (over 60%CVL) were observed in specific tasks being in agreement with perceived discomfort ratings. The increase of body temperature and weight loss in most cases remained within acceptable limits. For the most strenuous tasks, various ergonomic improvements were developed in consultation with workers and managers.