Anything that meets the following criteria is a waste and must be handled according to applicable local, state, and federal regulations. Regularly check chemical inventories for material that is:
- Spent material
- Unusable because it doesn't meet its required specifications
- Past its expiration date
- Unlabeled, and has been unlabeled for more than 10 days
- A container that once held chemicals
- Unwanted and intended to be discarded or recycled
- Answer the questions below.
If you answer NO to all the questions below, your chemical waste is not hazardous waste. Dispose of nonhazardous waste according to its type:
- Solids can go in the regular trash. DO NOT attempt to dissolve powders or salts and dispose of them in a drain. Chemically contaminated solid waste includes 3 categories that are packaged differently for disposal: lab trash, dry chemicals, and sharps. Read How to Store & Dispose of Extremely Hazardous Waste.
- Liquids can be poured down a drain, but may first require neutralizing or other conditioning. Read Sewer Disposal: What Can Go Down the Drain? for more information.
If you answer YES to any of the questions below, your chemical is hazardous chemical waste. Proceed to How To Store and Dispose of Hazardous Chemical Waste.
For empty containers that once held hazardous chemical wastes, read How to Dispose of Empty Hazardous Materials Containers.
- Does the waste consist of solid reagent chemicals in a manufacturer's container?
- Is the waste ignitable?
- Is the flashpoint less than or equal to 140°F or 60°C?
- Can the waste cause fire at standard temperature and pressure through friction, absorption of moisture, or spontaneous chemical changes?
- Is the waste an ignitable compressed gas?
- Is the waste an oxidizer?
- Will it release oxygen when reacting with another chemical?
- Will it react with organic materials such as oils, greases, solvents, paper, cloth, wood, etc., to ignite?
- Is the waste corrosive?
- Is it a liquid with pH less than or equal to 2, or greater than or equal to 12.5?
- Is it a solid with pH less than or equal to 2, or greater than or equal to 12.5 when mixed with an equal weight of water?
- Will it aggressively corrode steel?
- Will it destroy living tissue?
- Is the waste reactive?
- Is it normally unstable or subject to violent change?
- Does it react violently with water by forming potentially explosive mixtures or toxic gasses, vapors, or fumes?
- Is it a cyanide- or sulfide-bearing waste that can create toxic gasses, vapors, or fumes when exposed to pH conditions between 2 and 12.5?
- Can it detonate or explode when decomposing at standard temperature and pressure, when subjected to a strong initiating source, or when heated under confinement?
- Is the waste toxic? (Toxicity measures apply to all species.)
- Does it have an acute oral LD50 less than 2,500 milligrams per kilogram?
- Does it have an acute dermal LD50 less than 4,300 mg/kg?
- Does it have an acute inhalation LC50 less than 10,000 ppm as a gas or vapor?
- Does it have an acute aquatic 96-hour LC50 less than 500 milligrams per liter?
- Has the material shown through experience or testing to pose a hazard to human health or the environment because of its carcinogenicity (carcinogen, mutagen, teratogen), acute toxicity, chronic toxicity, bioaccumulative properties, or persistence in the environment?
Note: Many hazardous wastes are still hazardous at very low concentrations (less than 1%). Contact the EH&S Environmental Management Facility, (858) 534-2753, for assistance in determining if your low-concentration waste is hazardous.