The Chemical Reactivity Worksheet (CRW) is a free software program from The US NOAA (Also available as part of the larger CAMEO suite) that can be used to evaluate the chemical reactivity (Tendency of substances to undergo chemical change, such as heat generation, flame, explosion or byproducts) of thousands of common hazardous chemicals.  The CRW predicts potential hazards from mixing/blending chemicals and is designed to be used by emergency responders and planners, as well as industry professionals who use reactive chemicals, to minimize dangerous chemical incidents.

The chemical datasheets in the CRW database contain information about the intrinsic hazards of each chemical and whether it reacts with air, water, and/or other materials. Case histories of specific chemical incidents with references are also included.

Screenshot of a chemical search in the Mixture Manager screen of the Chemical Reactivity Worksheet.

The Mixture Manager allows you to search for chemicals in the CRW’s database, see a preview of the information on the chemical datasheets, and create a virtual mixture of chemicals. You can also access all the other features of the program from this screen, including the Compatibility Chart and hazards report for any mixture you create, reference information about the reactive groups used in the CRW, and information about absorbent incompatibilities with certain chemicals. The CRW also includes a neat reactivity prediction worksheet to virtually “mix” chemicals to simulate accidental chemical mixtures with warning about potentially hazardous byproducts and/or operating environments.
Screenshot of the Compatibility Chart in the Chemical Reactivity Worksheet, showing the predicted hazards of mixing a number of chemicals.

The Compatibility Chart shows the predicted hazards of mixing the chemicals in a mixture in an easy-to-use graphical interface. The reactivity predictions are color coded, and the cells on the chart can be clicked to find more information about specific predicted reactions. General hazard statements, predicted gas products, and literature documentation for the selected pair of chemicals are shown at the bottom of the chart.

NOAA has recently partnered with chemical industry experts to release a major update to the CRW (CRW version 3.0). This newest version of the program is the result of a two-year-long collaboration between NOAA chemical response specialists and expert chemists from the Dow Chemical Company.

All versions of the Chemical Reactivity Worksheet (CRW) were developed by NOAA’s Office of Response and Restoration, in collaboration with the Environmental Protection Agency and the Center for Chemical Process Safety.

Chemical Reactivity Worksheet Fact Sheet [PDF, 967 KB]: Learn more about basic features of the CRW in this short fact sheet.

Downloading the CRW

Download the appropriate version of the Chemical Reactivity Worksheet (CRW):