ASTM C1057-03

The procedures in this practice support the determination of the burn hazard potential for a heated surface. These procedures provide an estimate of the maximum skin contact temperature and must be used in conjunction with Guide C 1055 to evaluate the surface hazard potential.

The two procedures outlined herein are both based upon the same heat transfer principles. Method A uses a mathematical model to predict the contact temperature, while Method B uses a plastic rubber probe having similar heat transfer characteristics to the human finger to “measure” the contact temperature on real systems.

These procedures serve as an estimate for the skin contact temperatures which might occur for the “average” individual. Unusual conditions of exposure, incorrect design assumptions, subject health conditions, or unforeseen operating conditions may negate the validity of the estimations.

These procedures are limited to direct contact exposure only. Conditions of personal exposure to periods of high ambient temperatures, direct flame exposure, or high radiant fluxes may cause human injury in periods other than determined herein. Evaluation of exposures other than direct contact are beyond the scope of this practice.

Cold Surface Exposure—No consensus criteria exists for the destruction of skin cells by freezing. If, at some future time, such criteria are developed, extrapolation of the techniques presented here will serve as a basis for cold surface exposure evaluation.

1.1 This practice covers a procedure for evaluating the skin contact temperature for heated surfaces. Two complimentary procedures are presented. The first is a purely mathematical approximation that can be used during design or for worst case evaluation. The second method describes the thermesthesiometer, an instrument that analogues the human sensory mechanism and can be used only on operating systems.

Note 1&#8212lBoth procedures listed herein are intended for use with Guide C 1055. When used in conjunction with that guide, these procedures can determine the burn hazard potential for a heated surface.

1.2 A bibliography of human burn evaluation studies and surface hazard measurement is provided in the References at the end of Guide C 1055. Thermesthesiometer and mathematical modeling references are provided in the References at the end of this practice (1-5).

1.3 This practice addresses the skin contact temperature determination for passive heated surfaces only. The analysis procedures contained herein are not applicable to chemical, electrical, or other similar hazards that provide a heat generation source at the location of contact.

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.