# Vests with Radiative Cooling Materials to Improve Thermal Comfort of Outdoor Workers: An Experimental Study

## TL;DR

This study shows that vests with a special cooling coating can significantly improve thermal comfort for outdoor workers in hot environments.

## Contribution

The study introduces an optimal radiative cooling coating thickness and demonstrates its effectiveness in improving thermal comfort for outdoor workers.

## Key findings

- A radiative cooling coating of 160 μm thickness was found to be optimal for thermal performance.
- The coated vest reduced inner and outer surface temperatures by 5.54 °C and 4.37 °C, respectively.
- Thermal comfort improved significantly at a WBGT of 26 °C, with increased thermal sensation and comfort votes.

## Abstract

This study focuses on improving human thermal comfort in a high-temperature outdoor environment using vests with a radiative cooling coating. The effects of coating thickness on the radiative cooling performance were first evaluated, and an optimal thickness of 160 μm was achieved. Then, six subjects were recruited to evaluate the thermal comfort in two scenarios: wearing the vest with radiative cooling coatings, and wearing the standard vest. Compared with the standard vest, the coated vest decreases the maximum temperature at the vest inner surface and the outer surface by 5.54 °C and 4.37 °C, respectively. The results show that thermal comfort is improved by wearing radiative cooling vests. With an increase of wet bulb globe temperature (WBGT), the improving effects tend to decline. A significant improvement in human thermal comfort is observed at a WBGT of 26 °C. Specifically, the percentage of thermal sensation vote (TSV) wearing the cooling vest in the range of 0 to 1 increases from 29.2% to 66.7% compared with that of the untreated vest. At the same time, the average value of thermal comfort vote (TCV) increases from −0.5 to 0.2.