Toxic Release and Dispersion Models

Serious accidents (such as Bhopal) emphasize the importance of planning for emergencies and of designing plants to minimize the occurrence and consequences of a toxic release. Toxic release models are routinely used to estimate the effects of a release on the plant and community environments. 

An excellent safety program strives to identify problems before they occur. Chemical engineers must understand all aspects of toxic release to prevent the existence of release situations and to reduce the impact of a release if one occurs. This requires a toxic release model. 

identifying the release incident (what process situations can lead to a release This was described in sections 4-9 and 4-10), 

developing a source model to describe how materials are released and the rate of release (this was detailed in chapter 4), and 

estimating the downwind concentrations of the toxic material using a dispersion model (once the downwind concentrations are known, several criteria are available to estimate the impact or effect, as discussed in section 5-4). 

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Toxic release and dispersion models are an important part of the consequence modeling procedure shown in Figure 4-1. The toxic release model represents the first three steps in the consequence modeling procedure. These steps are... 

Table 5-6 (continued) Chapter 5 Toxic Release and Dispersion Models ... 

Chapter 5 Toxic Release and Dispersion Models Table 5-7 Emergency Exposure Guidance Levels (EEGLs) from the National Research Council (NRC) (all values are in ppm unless otherwise noted) ... 

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