This practice can be used to measure the insulation provided by different cold weather clothing systems using a heated manikin (see F 1291) and to predict the temperature rating for comfort using whole body heat loss models.

The temperature rating is for an ensemble—not an individual garment. However, manufacturers want to label cold weather garments with a temperature rating to help consumers select the product that will best meet their needs. Therefore, the standard is limited to garments that cover a substantial amount of body surface area such as jackets, coats, and insulated pants, coveralls, or snow suits. The temperature ratings of head wear, footwear, and hand wear cannot be determined with this practice.

The temperature predictions determined by this standard practice are for adults only. The physiology of children is significantly different from that of adults, so a modified heat loss model would need to be used to predict the comfort of children wearing outdoor clothing.

The temperature ratings determined by this standard practice and listed on garment labels are only guidelines for comfort and will be affected by the garments consumers wear with them, their activity level during wear, and individual differences in the physiological characteristics of people (for example, gender, age, body mass, etc.).

1.1 This standard practice covers the determination of the temperature rating of cold weather protective clothing ensembles. It involves measuring the insulation value of a clothing ensemble with a heated manikin in accordance with F 1291 and using a heat loss model to predict the lowest environmental temperature for comfort.

1.2 The predictive model used in this standard estimates the evaporative heat loss from a person wearing cold weather clothing as opposed to measuring the evaporative resistance on a sweating manikin. If a person is active and gets overheated in a cold environment, he/she can adjust the garments in order to dissipate excess heat.

1.3 The temperature ratings estimated by this standard practice are guidelines for thermal comfort that are designed to protect people from hypothermia when wearing cold weather protective garments. However, localized cooling, discomfort, and even frostbite could still occur at extremely low temperatures because clothing insulation is not evenly distributed over the body surface. In addition, some body parts (for example, ears, fingers, toes) have a high surface area relative to their mass, and consequently lose heat at a faster rate than other parts of the body.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.