Basic rules for safe storage of flammable materials include the following:

  • Store flammable and combustible liquids only in approved containers. Approval for containers is based on specifications developed by organizations such as DOT, the Occupational Safety and Health Administration (OSHA), the National Fire Protection Association (NFPA), or the American National Standards Institute(ANSI). Containers used by the manufacturers of flammable and combustible liquids generally meet these specifications.
  • Flammables stored in the open in the laboratory work area shall be kept to the minimum necessary for the work being done.
  • Do not store flammable liquids in domestic type refrigerators. Domestic type refrigerators are not recommended for laboratory use, even if flammable storage is not contemplated, since future research needs may require the use of flammables. Existing domestic refrigerators in labs must have a posting (similar to Figure 10.2) stating that no flammable storage is permitted. “Safety” refrigerators (Figure 10.3) are recommended for laboratories. These have the electrical contacts (door switch, light, thermostat, etc.) removed or exteriorized. “Explosion-proof” refrigerators (Figure 10.4) are not necessary except in unusual circumstances, such as within an inside storage room (for flammables) or other potentially hazardous atmospheres. Note that each of these is clearly labeled if it is for flammable material storage or explosion-proof.

Figure 10.2
Labels for lab refrigerators are available on the EHS website.

Figure 10.3
Safety refrigerator.

Figure 10.4
Explosion-proof refrigerators.

  • Flammable liquids must not block laboratory aisles or exits. Do not locate flammable storage cabinets near an exit or in the hallway.
  • Keep flammable liquids away from heat and direct sunlight.
  • Store flammable liquids in a way that prevents accidental contact with strong oxidizing agents (such as permanganates or chlorates).
  • University policy prohibits smoking in all University buildings; remove other sources of ignition from areas where flammable liquids are stored.
  • Maximum allowable size of containers for flammable and combustible liquids shall be in accordance with Appendix 10-A.
  • The potential fire hazard also depends on the total quantity of flammable and combustible liquids present within a laboratory unit (room) and the type of containers in which the liquids are stored. The maximum quantity allowed per laboratory unit is as follows:
    1. Shelf or open storage/use
      1. glass, approved plastic or metal: 10 gallons (37.9 liters)
      2. safety cans: 25 gallons (94.7 liters)
    2. Approved storage cabinets
      1. Class I: 30 gallons (113.6 liters)
      2. Class I, II, & III: 60 gallons (227.2 liters)
    3. Inside storage room (meeting NFPA Code recommendations)
      1. with sprinkler: 4-10 gal/ft²
      2. without sprinkler: 2-4 gal/ft²
    4. For laboratories located on upper floors within new or remodeled buildings, the limits for flammable and combustible liquids might be more restrictive due to the North Carolina Fire Prevention Code. Refer to Chapter 4 for more details, or contact EHS at 919-962-5507 if you have questions.