Chemical Storage in Laboratories

Let’s take the time to assess the chemicals stored in our laboratories and minimize hazards by cleaning out and re-evaluating how we store our chemicals. It’s all too often we hear about a chemical reacting spontaneously and creating an unexpected release and putting workers at risk of exposure to hazardous substances. Ensuring all chemicals are stored in a safe and consistent manner can minimize risk, and allow for effective response by emergency responders in times of unexpected releases.

Part of maintaining a safe environment in your laboratory is to maintain an up to date inventory of chemicals, as well as ensuring your chemicals are stored according to their hazard compatibility. Storing incompatible chemicals together can cause unwanted chemical reactions, which can lead to a release, fire, or even explosion.  These hazards are discussed further below.

General Guidelines for Safe Storage of Chemicals

  • Inventory Your Chemicals – maintain an up to date list of hazardous chemicals and conduct a periodic chemical assessment to remove chemicals that are unwanted or expired. Certain chemicals may degrade over time and become explosive. It’s important to remove expired chemicals. Consider barcoding or RFID tagging chemicals to help maintain a current inventory of chemicals.
  • Ensure chemicals are labeled with name, contents and hazards – replace missing or damaged labels. If chemicals are not from a manufacturer, ensure contents are clearly labeled.
  • Segregate incompatibles by hazard class. Keep incompatibles separate via distance and or separate cabinets.
  • Ensure chemicals stored on shelves are at eye level and have an anti-roll off lip.
  • Keep storage areas ventilated and at cool consistent temperatures.
  • Ensure appropriately rated fire extinguishers and spill kits are on hand.

Chemical storage DON’TS

  • Do not store chemicals alphabetically.
  • Do not store chemicals on the floor.
  • Do not store chemicals in the fume hood.
  • Do not store chemicals in sinks or near sinks.

Storage Requirements by Hazard


Segregate from organics, flammables, and combustibles (i.e, paper, wood, etc).


Store acids on low shelf or separate cabinet away from bases, organic acids, and flammables.


Store bases on low shelf or separate away from acids.


Store flammables in OSHA or NFPA and UL approved cabinet. Ensure cabinet is located away from sources of ignition. Store highly volatile flammable liquids in an explosion proof refrigerator.

Peroxide Formers

Peroxide formers are shock sensitive and may explode. Depending on the peroxide former, test chemicals every 3 to 12 months. Dispose if peroxide concentration is 100 ppm or more. Ensure new peroxide formers are labeled with date received, open date, as well as test dates. Store in airtight container, dark, cool, dry place.

Water Reactive 

Reacts violently with air and water. Avoid exposure to water and air. Store in a cool dry place.

Make sure all personnel are aware of all the chemicals hazards. Ensure they are trained in how to safely store the different classes of chemicals and what to avoid to prevent contamination. Chemicals can have more than one hazard, which is why it’s necessary to ensure proper storage.

Information on chemical compatibility can be obtained via: