Chemical Compatibility Matrix: Prevent Jobsite Reactions

The Invisible Hazard

On a congested construction site, storage space is at a premium. It is tempting to shove every chemical drum into the same container or cabinet. However, "incompatible storage" is a recipe for disaster. Mixing an oxidizer (like bleach or certain concrete hardeners) with a flammable solvent can create a fire or explosion without a single spark.

The Segregation Rules

OSHA and the EPA mandate strict segregation of incompatible materials.

1. Acids vs. Bases

Never store acids (e.g., Muriatic Acid) with bases (e.g., Ammonia, Concrete Cleaners). The reaction can release toxic chlorine gas or cause violent splattering.

2. Flammables vs. Oxidizers

Oxidizers provide the oxygen needed for a fire. Storing them next to fuel (Flammables) is building a bomb. Keep them separated by at least 20 feet or a non-combustible barrier.

3. Corrosives vs. Flammables

Corrosive containers can degrade over time, leaking fumes that can ignite flammable vapors.

Using a Compatibility Matrix

A compatibility matrix is a simple grid chart used to train workers.

Green (O): Safe to store together.

Red (X): Do not store together.

Yellow: Conditional/Separated.

Construction Example:

Gasoline (Flammable) + Oxygen Cylinders (Oxidizer) = X (Must be 20 ft apart).

Spray Paint (Aerosol) + Thinner (Flammable) = O (Compatible, same hazard class).

Storage Solutions

Separate Cabinets: Use yellow cabinets for flammables and blue cabinets for corrosives.

Secondary Containment: Use spill pallets to ensure that if two drums leak, their contents do not mix on the floor.

By training your logistics team to "Consult the Matrix" before unloading a delivery, you prevent chemical reactions that could shut down your site or injure your crew.

Related: [Chemical Compatibility Matrix](/tools/chemical-compatibility-matrix) · [GHS Rev 7 Storage](/blog/ghs-revision-7-converter-hazard-classes) · [Chemical Inventory](/