Ohio State University calorimeter

The Ohio State University (OSU) calorimeter (12) differs from the Cone calorimeter ia that it is a tme adiabatic instmment which measures heat released dufing burning of polymers by measurement of the temperature of the exhaust gases. This test has been adopted by the Federal Aeronautics Administration (FAA) to test total and peak heat release of materials used ia the iateriors of commercial aircraft. The other principal heat release test ia use is the Factory Mutual flammabiHty apparatus (13,14). Unlike the Cone or OSU calorimeters this test allows the measurement of flame spread as weU as heat release and smoke. A unique feature is that it uses oxygen concentrations higher than ambient to simulate back radiation from the flames of a large-scale fire. 

Rate of heat release measurements have been attempted since the late 1950 s. A prominent example of instrument design for the direct measurement of the sensible enthalpy of combustion products is the Ohio State University (OSU) calorimeter. This has been standardized by ASTM and a test method employing this technique (ASTM-E-906) is part of a FAA specification for evaluation of large interior surface materials. 

Smoke has usually been measured in the NBS smoke chamber. Such results cannot be correlated with full scale fire results and do not predict fire hazard. Rate of heat release (RHR) calorimeters (e.g. NBS Cone (Cone) and Ohio State University (OSU)) can be used to determine the best properties associated with fire hazard, as well as smoke. Results from the Cone RHR correlate with full-scale fire results. The best way to determine the fire hazard associated with smoke, for materials which do not burn up completely in a fire, is by using RHR to measure combined smoke and heat release variables, such as smoke parameter or smoke factor. 

Heat release equipment can be used to measure various parameters on the same instrument, in a manner generally relevant to real fires. The two most frequently rate of heat release (RHR) calorimeters used are the Ohio State University (OSU calorimeter) [4] and the NBS cone (Cone calorimeter)[5]. 

The heat generated in a fire is due to various chemical reactions, the major contributors being those reactions where CO and COg are generated, and O2 is consumed, and is defined as the chemical heat release rate (3). Techniques are available to quantify chemical heat release rate using FMRC s Flammability Apparatus (2-6), Ohio State University (OSU) Heat Release Rate Apparatus (J 3) and the NIST Cone Calorimeter (J jO. Techniques are also available to quantify the convective heat release rate using the FMRC Flammability Apparatus (2, 3) and the OSU Heat Release Rate Apparatus (J 3) The radiative heat release rate is the difference between the chemical and convective heat release rates (2,3). In the study, FMRC techniques were used. 

The heat of complete combustion is measured according to ASTM D 5865/ISO 1716 test methods [45,46]. The release rates of material vapors, heat, and various chemical compounds (including smoke) are measured according to ASTM E 906 (the Ohio State University Heat Release Rate, OSU-HRR, Apparatus), ASTM E 2058 (fire propagation apparatus) and ASTM E 1354/ISO 5660 (cone calorimeter) [45,46]. Smoke released in flaming and nonflaming fires of materials is also characterized... 

There are various standard methods available to assess the heat release rate. Widely used bench scale methods include the cone calorimeter which is based on oxygen consumption principle, such as ISO 5660 and ASTM E1354, and the Ohio State University (OSU) heat release apparatus (accepted for ASTM E906 Test Method for Heat and Visible Smoke Release Rates for Materials and Products) which measures heat release rate by the sensible enthalpy rise method. The large scale heat release tests using... 

There are seemingly endless programs to better understand fire tests and continually develop more realistic fire tests. Ohio State University has one with specific heat limits. The NIST has a cone calorimeter for heat release that is more sophisticated than the OSU one. And the National Institute of Building Science has an evolutionary version of the NIST smoke and toxicity test [361]. 

Prior to the widespread acceptance of the cone calorimeter, use was made of the Heat Release Calorimeter developed at Ohio State University, per ASTM E 906. The level of heat flux is adjustable, but not as extensively as with the cone calorimeter. Heat release from combustion is recorded throughout the period of ignition. Smoke density is measured similarly to the cone calorimeter. ASTM E 1354 and E 906 data correlate at comparable levels of heat flux input. 

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