Alleviation of Heat Strain by Cooling Different Body Areas during Red Pepper Harvest Work at WBGT 33℃

Abstract

The purpose of the present study was to examine the effects of different types of personal cooling equipments (PCE) on the alleviation of heat strain during red pepper harvest simulated in a climatic chamber. The experiment consisted of eight conditions: 1) Control, 2) Neck cooling scarf A with a cooling area of 68 cm², 3) Neck cooling scarf B (cooling area 154 cm²), 4) Brimmed hat with a frozen gel pack, 5) Cooling vest (cooling area 606 cm²), 6) Hat+Neck Scarf B, 7) Hat+Vest, and 8) Hat+Neck Scarf B+Vest. Twelve subjects worked a red pepper harvest simulated in a climatic chamber of WBGT 33℃. The result showed that rectal temperature (T_re) was effectively maintained under 38℃ by wearing PCE. Mean skin temperature (T_sk) and heart rate (HR) became more stable through wearing PCE. When wearing the ‘Hat+Scarf B+Vest’, particularly, T_sk and HR quickly decreased to the comfort level during the mid-rest stage. We confirmed that the vest with a cooling area of only 3.3% body surface area (BSA) was effective in alleviating heat strain in a simulated harvest work. Furthermore, the heat strain of farm workers can be considerably eliminated by the combination of the cooling vest, a scarf, and a brimmed hat, with the total cooling area of 4.2% BSA.