Standard Tests for Reactive Chemicals

In this section, tests to evaluate the hazards of reactive chemicals more accurately will be introduced. They are assumed to be the best tests available to date, even though they all may not be completely perfected yet. a. Pressure Vessel Test 51 (See Chapter 3) 

The pressure vessel test is used to examine the violence of thermal explosions. The test indicates whether a runaway reaction occurs when reactive chemicals in the vessel are heated by a fire or exposure to high temperature, or if the temperature of chemicals in the reactor rises abnormally. This test needs attention because the expulsion of chemicals from inside the vessel may mix with air and cause a mist explosion. 

The pressure vessel test is expected to be adopted as a standard test to check 

This test is not very accurate, although it is widely used to evaluate the hazards of organic peroxides. A new test procedure has been developed to classify the violence of decomposition of self-reactive chemicals into three levels. In the new test, only 1mm and 9mm orifices are used. Ten trials are conducted for each diameter, and the chemicals which explode 5 times or more are classified as medium and highly hazardous materials, respectively.This test has been adopted to classify hazardous materials under the Fire Services Law (See Chapter 3). 

We have sought a standard material. With 1mm orifices, a mixture of 80% AIBN and 20% inert alumina exploded 9 times while a 70% AIBN mixture never exploded. On the other hand, with 9mm orifices, a mixture of 80% BPO and 20% inert alumina exploded 10 times while a 70% BPO mixture never exploded. The boundary substance seems to fall somewhere between these mixtures. 

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