Hazardous Waste

Hazardous waste can be broken down into three groups: chemical, biological and universal.

This section deals with hazardous chemical waste. For biological decontamination and disposal guidelines, see the Biological Safety section on waste, or for the disposal of universal waste (including batteries, ink cartridges, and bulbs) see the Universal Waste Guidelines.

What is hazardous chemical waste?

Federal and state regulations define hazardous waste as any liquid, solid, semi-solid or gaseous material that is intended to be discarded and meets any of the characteristics listed below. Hazardous chemicals are substances that pose a threat to human health or the environment when improperly managed. Chemical waste is considered hazardous if it is listed on one of the lists of hazardous wastes found in federal or state regulations, or exhibits one or more of the four characteristics listed below.

Characteristics (as defined by Federal D List codes):

Ignitable

  • Flashpoint < 140° F
  • Capable of causing fire at standard temperature and pressure through friction, absorption of moisture, or spontaneous chemical changes
  • Is an ignitable compressed gas
  • Is an oxidizer

Corrosive

  • Liquid with pH < 2 or > 12.5
  • Solid that has pH < 2 or > 12.5 when mixed with equal weight of water

Reactive

  • Normally unstable and readily undergoes violent change
  • Reacts violently with water
  • Forms potentially explosive mixtures with water
  • Forms toxic gases, vapors, or fumes when mixed with water
  • Is a cyanide- or sulfide-bearing waste which, when exposed to pH conditions between 2 and 12.5, can generate toxic gases, vapors or fumes
  • Is capable of detonation or explosive decomposition if subjected to a strong initiating source or heated under confinement
  • Is readily capable of detonation or reaction at standard temperature and pressure

Toxic

  • Has an acute oral LD50 < 2,500 mg/kg
  • Has an acute dermal LD50 < 4,300 mg/kg
  • Has an acute inhalation LC50 < 10,000 ppm as a gas or vapor
  • Has an acute aquatic 96-hour LC50 < 500 mg/l
  • Has been shown through experience or testing to pose a hazard to human health or environment because of its carcinogenicity (carcinogen, mutagen, teratogen), acute toxicity, chronic toxicity, bioaccumulative properties or persistence in the environment