Kinetic information required to determine the worst case

3 Kinetic information required to determine the worst case 

To design a relief system, it is necessary to know how the system would behave under, runaway conditions (i.e., between the relief opening pressure and the maximum accumulated pressure) of the vessel). The appropriate temperatures at these pressures are different depending on whether or not the system is tempered or untempered. 

For vapour pressure systems this will depend on the rate of temperature rise. Since the reaction will be tempered, the rate which is of interest is that at the average temperature between the relief pressure and the maximum accumulated pressure. 

For gassy systems, this will depend on the rate of pressure rise in a closed system (rate of gas generation). Since gassy systems are untempered, the rate of interest is the maximum rate. This is likely to be at close to the maximum temperature reached by the runaway. 

For hybrid systems this will be a combination of both the rate of temperature and pressure rise.- Whether these should be measured at the relief pressure 

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