Step four: What are the hazards (characteristics)?
Waste characteristics are measurable, physical characteristics that might make your waste hazardous to you or the environment.
The four groups of characteristic wastes are:
- Ignitable (D001)
- Corrosive (D002)
- Reactive (D003)
- Toxic (D004 to D043)
How to determine waste characteristics
Once you determine if your waste designates for any listed codes — K, F, P, or U — you will need to determine its characteristic hazards.
- Look at the Safety Data Sheet (SDS or MSDS) for each product that goes into your waste stream. If any products that go into your waste stream have characteristic hazards, then you can assume the entire waste stream also meets the criteria for those hazards, unless you can provide other information about the mixture’s chemistry.
For example: If a product in your waste stream is ignitable, you can assume the entire waste mixture is ignitable, unless you can provide other information about the mixture’s chemistry.
- Label your waste so anyone handling the waste knows its hazards.
What if you can't determine waste characteristics?
Sometimes you don’t know enough about your waste to determine its characteristic hazards. If this is the case:
- Test for ignitability, corrosivity, or toxicity by sending a sample of your waste to a laboratory.
- Reactivity cannot be tested and must be determined through knowledge about your waste.
Learn more about dangerous waste characteristics (WAC 173-303-090).
Groups of characteristic wastes
Ignitable: Code D001
Ignitable wastes easily catch fire and continue to burn for a long time. Ignitable wastes have a D001 code.
- Ignitable liquid wastes have a flashpoint of 140 degrees F or less.
- Ignitable solids catch fire and burn vigorously through friction, absorption of moisture, or spontaneous chemical changes.
- Compressed gases and oxidizers are also classified as ignitable under certain conditions.
Corrosive: Code D002
Corrosive wastes are acids or bases that are capable of corroding metal containers, such as storage tanks, drums, and barrels. They can seriously damage skin, lungs, and other tissue. These wastes have a D002 code.
A liquid is corrosive if it:
- Has a pH less than or equal to 2, or
- Has a pH greater than or equal to 12.5, or
- Corrodes steel at a specified rate.
Bleach and battery acid are common examples.
A solid or semisolid is corrosive if it:
- Has a pH of less than 2, or
- Has a pH greater than 12.5.
Solid corrosives are also a Washington state-only waste with the waste code WSC2.
Reactive: Code D003
Reactive wastes are unstable under "normal" conditions. They can cause explosions, toxic fumes, gases, or vapors when heated, compressed, or mixed with water. These wastes have a D003 code.
- Lithium-sulfur batteries.
Toxic: Codes D004 to D043
Toxic wastes are harmful or fatal when ingested or absorbed. When toxic wastes are land-disposed, contaminated liquid may leach from the waste and pollute groundwater. There are 40 chemicals on the federal toxicity characteristic list (the “D list”) (see WAC 173-303-090(8)(c)), each with a unique waste code. If your waste contains one of these 40 chemicals at a concentration equal to or greater than the threshold level, you must use the waste code that corresponds with that chemical.
- Heavy metals.
- Organic chemicals.
The Toxicity Characteristic Leaching Procedure (TCLP) is a laboratory test that measures the likelihood toxic chemicals will leach out of a waste in landfill conditions. If the waste exceeds threshold TCLP levels for characteristic chemicals, the waste is a dangerous waste. Learn how to choose an analytical laboratory to test waste.