Assessing skin thermal injury risk in exposure tests of heating until flight

TL;DR

This paper develops a model to assess skin thermal injury risk during electromagnetic exposure tests by relating injury parameters to observable flight action timing, overcoming measurement challenges.

Contribution

It introduces a normalized thermal damage model based on flight action timing, enabling injury risk assessment without direct measurement of absorbed power or volume thresholds.

Findings

Thermal damage parameter linked to flight action timing.

Model allows investigation of parameter effects.

Provides a framework for injury risk assessment.

Abstract

We assess the skin thermal injury risk in the situation where a test subject is exposed to an electromagnetic beam until the occurrence of flight action. The physical process is modeled as follows. The absorbed electromagnetic power increases the skin temperature. Wherever it is above a temperature threshold, thermal nociceptors are activated and transduce an electrical signal. When the activated skin volume reaches a threshold, the flight signal is initiated. After the delay of human reaction time, the flight action is materialized when the subject moves away or the beam power is turned off. The injury risk is quantified by the thermal damage parameter calculated in the Arrhenius equation. It depends on the beam power density absorbed into the skin, which is not measurable. In addition, the volume threshold for flight initiation is unknown. To circumference these difficulties, we normalize the formulation and write the thermal damage parameter in terms of the occurrence time of flight action, which is reliably observed in exposure tests. This thermal injury formulation provides a viable framework for investigating the effects of model parameters.