Nomograph Linking Decomposition Temperature with Arrhenius

Fig 2 Nomograph Linking the Decomposition Temperature Td °K with the Arrhenius Activation Energy Ea in kcal/mole (Ref 2) 

Fig 3 Example of Use of Reaction Hazard Index with Methane, Ethylene, and Acetylene (Ref 2) 

Comparison of NFPA Reactivity Rating with the Reaction Hazard Index (Ref 2  

The NFPA Reactivity Ratings represent the consensus of a committee of experts, and because of the number of factors taken into consideration the values agreed upon might in some instances border on the next higher (or lower) value, and thus be indeterminate by one unit. Hence, acetylene (No 72) rightfully carries the maximum, hazardous NFPA Reactivity Rating of 4, and based on the evidence in Table 3, it is not unreasonable that vinylacetylene (No 68) should also 

Data Sources, Reaction Hazard index, and National Fire Protection Association Reactivity Rating 

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