Reactivity Hazard Management Expert System

The US Chemical Safety and Hazard Investigation Board (CSB) conducted a study of the contributing factors to 167 major reactive chemical accidents.  The findings were somewhat surprising:

• More than half of the accidents included materials and processes that were not covered by process safety regulations
• More than half of the accidents involved materials that themselves were not considered reactive hazards by the NFPA rating system, and only 10% involved materials with NFPA ratings 3 or 4 (i.e. significant reactive hazards)
• More than 90 % of all incidents involved reactivity hazards published in commonly available reference books
• More than half the accidents occurred at smaller companies with more resource constraints
• 30% of all accidents occurred at companies that used chemicals but did not consider themselves to be chemical companies

The CSB further observed that Material Safety Data Sheets generally show only NFPA reactivity data, and frequently do not advise the user on instability and incompatibility hazards.  Among many recommendations presented as a result of this study, CSB recommended that the Center for Chemical Process Safety (CCPS) publish guidance which would help guide chemical engineers and others engaged in handling potential reactive hazards in identifying these hazards and preventing them.  To this end, CCPS published the book “Essential Practices for Managing Chemical Reactivity Hazards” and secured funding to make this book available for online browsing.  CCPS then embarked on a more ambitious task to develop the Reactivity Evaluation and Screening Tool (REST), a free online expert system to help companies with limited resources identify chemical reactivity hazards in their facilities.  REST incorporates expert guidance consolidated from dozens of the worlds experts in chemical reactivity hazard management, and provides access to a broad public database of the reactivity hazards of pure components and mixtures.

The purpose of this paper is to introduce and encourage the free use of REST and to discuss the basic principles of reactive chemical hazard screening.