- Author
- Knox, F. S., III | Wachtel, T. L. | Knapp, S. C.
- Title
- Mathematical Models of Skin Burns Induced by Simulated Postcrash Fires as Side in Thermal Protective Clothing Design and Selection. Final Report.
- Coporate
- Army Aeromedical Research Lab., Fort Rucker, AL
- Sponsor
- Army Medical Research and Development Command, Frederick, MD
- Report
- USAARL 78-15, June 1978, 31 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- skin | animals | mathematical models | simulation | postcrash fires | protective clothing | heat transfer | exposure time
- Identifiers
- flight suits
- Abstract
- The design and selection of thermal protective clothing takes into account many factors, e.g., appearance, comfort, durability, cost, and thermal protective capability. To aid in determining the appropriate balance among these factors, thermal protective capability must be measured in a quantitative and clinically meaningful way. To provde such a valid assessment of thermal protective capability, tow mathematical models were developed to predict skin burn damage based on data derived from 95 domestic white pigs exposed to simulated postcrash fires. The first model, a multidiscriminate statisticsl model derived from experimental data, was used to determine the importance of many variables., e.g., incident heat flux, exposure time, initial skin temperature, and color of the skin. The second, an analytical model, assumes that tissue damage proceeds as a first order chemical reaction dependent on tissue temperature, and that total damage is merely the time integral of tissue damage during heating and cooling. It also takes into account tissue water boiling and thermal shrinkage which alter burn depth in more severe burns. The predicted survivability. Predictions of changes in survivability allow rational judgments to be made regarding the effectiveness of implementing proposed flight suit clothing fabric and design changes. Progress toward supplanting the USAARL bioassay method for thermal fabric evaluation by laboratory methods involving heat sensors and a mathematical model is encouraging. Implementation will require minor changes in the analytical model, BRNSIM, to make its output conform more closely to observed tissue temperatures and will require the addition of a routine to convert sensor temperatures to heat flux. Consideration of survivability will require more precise clinical data relating burn depth to clinical outcome.