I'm sure your model is a reasonable approximation, Bleve, but I notice that it assumes that the fire is burning at one rate of heat output from the outset. Users should be aware that this is likely to lead to conservative results. In many cases such results will be more than adequate but there are more realistic models available. Mind you, I'm not claiming that any of them give accurate results.
I also notice, Bleve, that the formula for tau m seems to be the ratio between the mass of ambient air in the space and the mass flow rate of smoke per second. But the figure used for the mass flow rate of smoke is correct only when the smoke layer has zero thickness (because H^5/3 is used). Is this correct?
Also, any users of models such as these should be aware that they should not be used for spaces larger than about 1,000 sq m in area (that would be stretching the limits of feasible extrapolation) and they probably start to lose reliability in spaces smaller than this - maybe at around 500 sq m.
Also, why is this under 'service training or recruitment'?
Stu
