Chemical Storage Cabinets
Specialized types of storage cabinets must be used in laboratories in order to separate incompatible chemicals from one another and to ensure safe storage. All chemicals must be stored in a secure container, preferably within enclosed cabinets. Periodically check shelves and supports in all chemical storage cabinets for corrosion or other signs of damage.
Flammable Storage Cabinets
Flammables not in active use should be stored inside a flammable storage cabinet. Flammable storage cabinets should be used for all labs that use flammable chemicals. No more than 10 gallons of flammable chemicals can be stored outside of a flammable cabinet.
The cabinet design must meet National Fire Protection Association (NFPA) 30 & Occupational Safety and Health Administration (OSHA) 1910.106 standards. The purpose of designing to these codes is to minimize the risks caused by a fire following the combustion of flammable materials that were exposed to a source of flame or spark. Flammable cabinets have features such as flame arresters, leak-proof sills, and highly visible signage.
Flammable storage cabinets are designed to protect the contents from the heat and flames of external fire rather than to confine burning liquids within. They can perform their protective function only if used and maintained properly. Always make sure that the door properly and fully closes.
Cabinets are typically designed with double-walled construction and doors which are two inches above the base (the cabinet is liquid-proof up to that point). Cabinet doors should be self-closing.
Metal Flammable Storage Cabinet Features Include:
- Bottom, top and sides of cabinet must be at least No. 18-gauge sheet iron
- Cabinet must be double walled with one and one-half inch airspace
- Joints must be riveted, welded or made tight by some equally effective means
- Door must have a three-point latch
- Door sill must be raised at least two inches above the cabinet bottom to retain spilled liquid within the cabinet
Wood Flammable Storage Cabinet Features Include:
- Bottom, top and sides of cabinet must be constructed of exterior-grade plywood at least one inch thick
- Plywood must not break down or delaminate under fire conditions
- Joints shall be rabbeted and fastened in two directions with flathead wood screws
Acid Storage Cabinets
Acids should be kept in an acid storage cabinet specially designed to hold them. Such cabinets are made of plastic or metal coated with epoxy enamel to protect against corrosion. If not provided as part of the cabinet, use polyethylene trays to contain small spills. If your lab does not have an acid cabinet, acids can be stored in a wooden cabinet inside a plastic tub for containment. Nitric acid must always be stored away and separate from other acids.