Air-conditioning vests circulate cool air to minimize temperature-related stress and fatigue. The Vortec PAC diffuses cooled airflow around the worker’s torso. The vests use a vortex tube to reduce the temperature of the air circulating through the vests by as much as 60°F cooler than ambient. Plasticized vests are available in three sizes and provide continuous cooled or warmed air through the perforated lining. According to the manufacturer, they do not restrict movement nor absorb sweat or other contaminants. The vests can be worn under other protective clothing. Dual-action models can be switched from cold to hot airflows.