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Improved Real-Scale Fire Measurements Having Meaningful Uncertainty Limits (NISTIR 6588)



William M. Pitts, George W. Mulholland


The National Institute of Standards and Technology has undertaken a long-term effort designed to improve our ability to make experimental measurements having quantiftable uncertainties in real-scale fire environments. The adopted approach has two components. The first focuses on quantifying the uncertainties associated with existing techniques commonly employed to characterize real-scale fire environments. Measurements considered thus far include gas temperature using thermocouples, smoke mass concentration using optical extinction, rate of heat release using the NIST furniture calorimeter, and radiative and total heat transfer using heat flux gauges. The measurement of smoke mass concentration is discussed in some detail as an example of how a measurement approach can be modified to provide improved information while at the same time providing reliable estimates of the uncertainty. The second component is centered on the development of new approaches for measurements in fire environments which offer both improved measurement capability and quantification of uncertainties. An effort to combine near-infrared laser diode absorption spectroscopy with fiber optic coupling for local time-resolved measurements of carbon monoxide concentration in fire environments is discussed briefly.
NIST Interagency/Internal Report (NISTIR) - 6588
Report Number


fire safety, fire research, fire measurements, thermocouples, smoke meters, heat release rate, furniture calorimeters, heat flux


Pitts, W. and Mulholland, G. (2000), Improved Real-Scale Fire Measurements Having Meaningful Uncertainty Limits (NISTIR 6588), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 23, 2024)


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Created November 1, 2000, Updated November 10, 2018