In 2005, a university student was helping unload a shipment of hexane into a solvent storage cabinet when a shelf broke, cutting his arm and releasing fumes into the lab. Five-minutes after the students decided to evacuate the premises, there was an explosion that destroyed the lab and damaged an adjacent one. It took local area firefighters more than an hour to extinguish the blaze. Fortunately, there were no casualties as a result.
As evidenced by this incident, something as easy to overlook as the integrity of the chemical cabinet shelving can prove to be catastrophic. To ensure that a similar accident doesn’t occur in your own lab, the Environmental Safety Division of the University of Georgia has identified 8 fundamental things to include in your chemical storage plan.
8 Fundamentals to include in your Chemical Storage Plan:
1. Chemicals should be stored according to hazard class (ex. flammables, oxidizers, health hazards/toxins, corrosives, etc.).
2. Store chemicals away from direct sunlight or localized heat.
3. All chemical containers should be properly labeled, dated upon receipt, and dated upon opening.
4. Store hazardous chemicals below shoulder height of the shortest person working in the lab.
5. Shelves should be painted or covered with chemical-resistant paint or chemical-resistant coating.
6. Shelves should be secure and strong enough to hold chemicals being stored on them. Do not overload shelves.
7. Personnel should be aware of the hazards associated with all hazardous materials.
8. Separate solids from liquids.
Below are examples of chemical groups that can be used to categorize storage. Use these groups as examples when separating chemicals for compatibility. Please note: reactive chemicals must be more closely analyzed since they have a greater potential for violent reactions. Contact Laboratory Safety if you have any questions concerning chemical storage.
- Make sure that all acids are stored by compatibility (ex. separate inorganics from organics).
- Store concentrated acids on lower shelves in chemical-resistant trays or in a corrosives cabinet. This will temporarily contain spills or leaks and protect shelving from residue.
- Separate acids from incompatible materials such as bases, active metals (ex. sodium, magnesium, potassium) and from chemicals which can generate toxic gases when combined (ex. sodium cyanide and iron sulfide).
- Store bases away from acids.
- Store concentrated bases on lower shelves in chemical-resistant trays or in a corrosives cabinet. This will temporarily contain spills or leaks and protect shelving from residue.
- Approved flammable storage cabinets should be used for flammable liquid storage.
- You may store 20 gallons of flammable liquids per 100 sq.ft. in a properly fire separated lab. The maximum allowable quantity for flammable liquid storage in any size lab is not to exceed 120 gallons.
- You may store up to 10 gallons of flammable liquids outside of approved flammable storage cabinets.
- An additional 25 gallons may be stored outside of an approved storage cabinet if it is stored in approved safety cans not to exceed 2 gallons in size.
- Use only explosion-proof or intrinsically safe refrigerators and freezers for storing flammable liquids.
- Peroxide-forming chemicals should be stored in airtight containers in a dark, cool, and dry place.
- Unstable chemicals such as peroxide-formers must always be labeled with date received, date opened, and disposal/expiration date.
- Peroxide-forming chemicals should be properly disposed of before the date of expected peroxide formation (typically 6-12 months after opening).
- Suspicion of peroxide contamination should be immediately investigated. Contact Laboratory Safety for procedures.
- Water reactive chemicals should be stored in a cool, dry place.
- Do not store water reactive chemicals under sinks or near water baths.
- Class D fire extinguishers for the specific water reactive chemical being stored should be made available.
- Make sure that all oxidizers are stored by compatibility.
- Store oxidizers away from flammables, combustibles, and reducing agents.
- Toxic compounds should be stored according to the nature of the chemical, with appropriate security employed when necessary.
- A "Poison Control Network" telephone number should be posted in the laboratory where toxins are stored.