Critical considerations on the use of a bi-directional probe in heat release measurements

In various medium to large scale fire test equipment, such as the ISO room corner (RC) test and more recently the single burning item (SBI) test, the mass flow measurement of the combustion gases plays a key role in the determination of the heat release rate and smoke production rate. To date a bi‐directional low‐velocity pressure probe has been used to calculate this flow based on a differential pressure measurement on the axis of the exhaust duct. The objectives of this paper were to evaluate this bi‐directional probe—and the modified SBI version—when used for measuring flows in exhaust ducts. Recommendations are given on the future use of pressure probes measuring exhaust gas mass flows. Copyright © 2005 John Wiley & Sons, Ltd.