Cooling vests are typically used underneath (or between) clothing and an outer protective garment as means to prevent and/or delay the onset of heat-related illness and stress. The two primary cooling methods are: active cooling via the use of frozen/chilled inserts or compartments, and passive cooling via the use of specialized textiles designed to transfer heat away from the body. Cooling vests are not routinely used in remote locations or for short term site visits, as duration in PPE is usually limited in those scenarios and/or the operators are better conditioned and accustomed to the use of PPE.