Chemical Storage

General Guidelines

Proper chemical storage is a key component in laboratory safety. The following guidelines are taken from Prudent Practices in the Laboratory (NRC) and Chemical Storage Plan for Laboratories (College of American Pathologists).

Do:

  • Make sure all chemicals are clearly labeled and both label and container are in good condition.
  • Dispose of (via Hazardous Waste) expired, unused, or compromised chemicals.
  • Physically separate incompatible chemicals; separate liquids from solids.
  • Limit storage of chemicals on benchtops.
  • Segregate by hazard class:
    • Health Hazards (Toxins, Poisons, Carcinogens, etc.)
    • Corrosives (Additionally separate acids from bases; separate inorganic and organic acids)
    • Reactives/Oxidizers
    • Flammables (Should be stored in flammable cabinet)
    • General Storage (e.g., salts, media, and other routine dry chemicals - relatively modest hazards)
  • Date when received and again when opened/prepared. (Dating containers is especially important for chemicals with a short shelf life like ethyl ether which, because of its explosion hazard, should not be kept for more than 12 months after being opened and must never be kept past its expiration date).

Do not:

  • Store large quantities of chemicals on benchtops
  • Store large quantities chemicals in fume hoods or under sinks.
  • Expose chemicals to heat or direct sunlight.
  • Store hazardous materials above shoulder height of shortest person in lab.
  • Store liquid chemicals above eye level.

Hazard Specific Storage Rules

Health Hazards

  • Separate toxins and poisons from other chemicals in a location labeled Toxins or Poisons.

Corrosives

  • Store large bottles on a low shelf or in a corrosives cabinet.
  • Segregate oxidizing acids (ex. nitric acid, perchloric acid) from organic acids, flammables, and combustible materials.
  • Separate acids from bases and active metals.
  • Segregate acids from chemicals which can generate toxic gases on contact (e.g., sodium cyanide).
  • Segregate perchloric acid from reducing agents and organic compounds.
  • Store in chemical resistant trays.
  • Store glacial acetic acid in flammables cabinet, away from oxidizing acids.

Reactives/Oxidizers

  • Store water-reactive chemicals in a cool and dry place.
  • Store oxidizers away from flammables, combustibles, and reducing agents (zinc, alkaline metals, etc.).
  • Store peroxide-forming chemicals in an airtight container in a cool, dry, dark place.
  • Peroxide-forming chemicals should be disposed of within 12 months of opening or by manufacturer’s expiration date.
  • Shock sensitive and detonable materials should be stored in a secondary container, large enough to hold entire contents in case of breakage.
  • Store liquid organic peroxides at the lowest possible temperature consistent with solubility and/or freezing points.

Flammables/Combustibles

  • Store flammable liquids in flammable storage cabinet.
  • Do not store flammable liquids in domestic refrigerators or freezers.
  • Store away from ignition and heat sources.
  • Stay within NFPA rules for volume of flammables: 
    • Maximum for any lab is 120 gallons.
    • With flammable safety cabinet - 10 gal/100 sq. ft. un-sprinkled or 20 gal/100 sq ft of sprinkled area.
    • Without flammable safety cabinet - 10 gallons in original container & 25 gallons in 2.5 gallon or smaller safety cans.

Gas Cylinders

  • Strap or chain individual cylinders securely to a stationary object (benchtop, wall, etc.).
  • Cap cylinders not in use.
  • Separate incompatible compressed gas cylinders (oxidizing gases separate from flammable gases).
  • Segregate empty cylinders from full ones.

Chemical manufacturers include storage information on the label. This may be done with a color code or pictogram to indicate hazards.

Chemical Incompatibility Tables

Chemical incompatibility tables provide additional guidelines for proper chemical segregation based on chemical and physical hazards.