Total smoke released

Rate of heat calorimeters can be used to measure a number of the most important fire hazard parameters, including the peak rate of heat release, the total heat release, the time to ignition and smoke factor (a smoke hazard measure combining the total smoke released and the peak RHR [14, 18-20]). The smoke factor will give an... 

This parameter, the smoke parameter, is based on continuous mass loss measurements, since the specific extinction area is a function of the mass loss rate. A normal OSU calorimeter cannot, thus, be used to measure smoke parameter. An alternative approach is to determine similar properties, based on the same concept, but using variables which can be measured in isolation from the sample mass. The product of the specific extinction area by the mass loss rate per unit area is the rate of smoke release. A smoke factor (SmkFct) can thus be defined as the product of the total smoke released (time integral of the rate of smoke release) by the maximum rate of heat release [19], In order to test the validity of this magnitude, it is important to verify its correlation with the smoke parameter measured in the Cone calorimeter. 

Note TTI, time to ignition PHRR, peak of heat release rate MAHRE, maximum average rate of heat emission THR, total heat release EHC, effective heat of combusion TSR, total smoke released. 

Several standard room/corner test protocols are now available and are specified in codes and regulations for qualifying interior finishes. For example, U.S. model building codes require that textile wall coverings for use in unsprinklered compartments meet specific performance requirements when tested according to NFPA 265. The principal requirement of these tests is that flash-over does not occur. The same codes also require that all other interior wall and ceiling finish materials comply with requirements based on NFPA 286, including a limit on the total smoke released. 

The cone calorimeter,71 which is a dynamic flow-through fire test, can also be used to assess smoke obscuration. The rankings tend to be quite different from those found with the static smoke chamber and are much more realistic. Several empirical parameters have been proposed to make this compensation for incomplete sample consumption, including one called the smoke factor (SmkFct), determined in small-scale RHR calorimeters.188 It combines the two aspects mentioned earlier the light obscuration (as the total smoke released) and the peak RHR. 

Figure 13.7. Total smoke release vs. time. [Data from Herbert M J, Flame Retardants 96. Conference proceedings, London, 17th-18th Jan.1996,157-72.]...

In the course of experiment, the four coal samples burning characteristics are measured, the parameters include CO, heat release rate (HRR), total heat release (THR), smoke produce rate (SPR) and total smoke release (TSR), and so on. Each parameter is shown in Figure 1-6. 

Smoke produce rate (SPR) and total smoke release (TSR)... 

Fourthly, in respect of smoke produce rate and total smoke release, there is certain difference that the first coal sample taken from 11605 working face in west wing is the highest, and the first coal sample taken from 11606 working face in east wing takes second place, and there is little difference in the others coal samples. 

Fig. 12.14 The smoke release (SR) and total smoke released (TSR) during burning of polypropylene with Mg(OH)2, the cone radiancy 35 kW/m. Numbers denote wt% of Mg(OH)2...

Hapuarachchi [65] also measured the heat release rates (HRR) of PP and its different nanocomposites by cone calorimeter (Figure 12.24). The time to ignition was slightly anticipated probably due to an increased thermal conductivity induced by the presence of CNTs. Nevertheless, the peak of HRR experienced a reduction of 80%, from 1933 to 355kW/m2. The similar values of total smoke release (CO and CO2) suggested that the difference between... 

Note. TTI time to ignition, TOP time of flame out, peak HRR peak heat release rate, THR total heat release, TSR total smoke release, and TCOR total CO release. 

The total smoke released (TSR) is minimal for the composite at 20 wt% AlOOH. However, the total CO released (TCOR) increases during combustion when the concentration of AlOOH in PMMA also increases. 

TSR total smoke release, and 5bet BET specific surface area of alumina. 

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