Smoke spread

Accident simulation Large-scale accidents normally cannot be staged for experimental purposes. It is impossible to put a building on fire in order to see how smoke spreads. In this case, numerical simulation is the sensible approach. 

Depending on the requirements of local fire officers, statutory regulations and insurance bodies (or any other documents or bodies having jurisdiction), there may well be a need to address the clearance of smoke from escape routes, the control of smoke spread generally and the removal of smoke during and after firefighting activities. 

The dispersion coefficient E shown in Eq. (27) is not equal to the diffusion coefficient defined in the earlier parts of this entry. The dispersion coefficient does have the same dimensions of length2 per time as the diffusion coefficient. Its function is to describe how fast the smoke spreads, just as the diffusion coefficient describes how fast the solute spreads. However, the dispersion coefficient E is much more a function of physics and much less a function of chemistry. For example, we expect the diffusion... 

Code-required construction for control of smoke spread, lire stopping, etc. 

If a shaft is used for evacuation during emergency, e.g. fire, the vertical shaft depth should be lower than the lowest layer. The deep depth can avoid the smoke spreading into the evacuation shaft during a fire disaster. 

Low risk - areas where there is minimal risk to people s lives, where the risk of fire occurring is low, or the potential for fire, heat and smoke spreading is negligible and people would have plenty of time to react to an alert of fire. 

At Zaporozhe NPP, the main control room and emergency control room has a common ventilation circuit for Units 1 to 4 while they are separated for Units 5 and 6. This disposition cannot ensure habitability in case of fire in locations ventilated by this circuit because of the smoke spreading. 

In any ceiling void where a long corridor (over 12 m) has been subdivided to limit fire or smoke spread... 

Providing automatic fire detection in zones often results in a quicker identification of the location of the fire and can provide an overview of the extent of fire and smoke spread throughout the building which will aid evacuation and response. 

Rapid fire and smoke spread >- Spreading to adjacent properties... 

Worked example 3 - Rapid fire and smoke spread in the workplace... 

This model does a good job of predicting the general shape of the smoke plume. It predicts that the maximum smoke concentration Sj4nDappx) does drop as x increases. It does predict that the smoke spreads out in a roughly Gaussian profile, just as is observed. Thus diffusion theory apparently can be applied successfully to the release of pollutants. 

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