Measurement of Effective Temperature Range of Fire Service Thermal Imaging Cameras
Francine K. Amon, Nelson P. Bryner
The use of thermal imaging cameras (TIC) by the fire service is increasing as firefighters become more aware of the value of these tools. The National Fire Protection Association (NFPA) is currently developing a consensus standard for design and performance requirements of TIC as used by the fire service. The National Institute of Standards and Technology facilitates this process by providing science-based performance metrics and test methods to the NFPA technical committee charged with the development of this standard. A suite of imaging performance metrics and test methods, based on the harsh operating environment and limitations of use particular to the fire service, has been proposed for inclusion in the standard. The Effective Temperature Range (ETR) measures the range of temperatures that a TIC can view while still providing useful information to the user. Specifically, water and extreme heat in the field of view tend to inhibit a TIC s ability to discern surfaces having intermediate temperatures, such as victims and firefighters. The ETR measures the contrast of a target having alternating 30 oC and 40 oC bars while an increasing temperature range is imposed on other surfaces in the field of view. The ETR also indicates the thermal conditions that trigger a shift in integration time common to TIC employing microbolometer sensors. The reported values for this imaging performance metric are the temperature range at which the TIC no longer responds to further increases in temperature, and the hot surface temperature at which the TIC shifts integration time.
SPIE Defense and Security Symposium
fire service, performance metric, termal imaging camera, test method, TIC