Extent of Potential Hazard Rating

Materials which are normally stable even under fire exposure conditions and are not reactive with water 

The lower third of the chart (up to Tq-Tj = 1,000°K) contains hazardous explosives or materials with an NFPA rating of 3 or 4 (shock sensitive explosive materials). The single exception is hydrogen cyanide with an NFPA rating of 2 (unstable, capable of violent chemical change, but does not detonate) 

The middle third of the chart (from 1000 to 2000 °K) contains materials that are explosive and have NFPA ratings that range 

The upper third of the chart (above 2000 °K) contains materials that are almost entirely normally stable with an NFPA rating of 0. The two exceptions are 1,3-butadiene and styrene with NFPA ratings of 2 (normally unstable and can undergo violent reaction, but do not detonate) 

The results of the thermodynamic calcns and the compounds for which they were made,. together with the NFPA ratings are shown in the following Table (taken from Ref 1)  

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The male-female hazard ratio is estimated at 4.2, implying male hazard rates of on average say four times the female hazard rate. It is likely that this large hazard ratio is to some extent due to selection of male workers in jobs with high hazard potential (in for instance construction work and industry). A remarkable hazard-age pattern is observed. An initial specification of the model with separate fixed-effects for all ages revealed that the hazard rate peaks at the age of 19 and subsequently declines with age in the interval 20-29. For workers older than 30 the hazards rate increases steadily as they grow older. On the basis of this observation separate linear effects were estimated for the interv s 15-19, 20-29 and 30-64. Results are displayed in Table 1. 

Parent molecules, metabolites, and transformation products may undergo further transformation (Figure 9.3). A few API compounds can be hydrolyzed, such as some of the (3-lactam antibiotics [44]. Stable degradation products may result from these processes. Often the toxicity and potential environmental hazards of such transformation products are not known. Even if APIs are eliminated to some extent, they may still persist in the aquatic environment if the rate of input is higher than the rate of removal. The resulting situation in such cases is reminiscent of persistent pollutants. 

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