Dangerous waste designation

These are provided by the product manufacturer and list information like pH, flashpoint, and other physical specifications. Some SDS also have information on a product’s toxicology or stability (e.g., if it’s reactive or ignitable).

Be aware that:

• A waste may not have the same properties or constituents as the original product.
• Even if the SDS says the product is NOT hazardous, you still need to check if it qualifies as a dangerous waste.

Common examples, but not an exhaustive list, of exempt wastes include:

• Reclaimed commercial chemical products (see WAC 173-303-016).
• Pulping liquors reused for pulping (see WAC 173-303-017).
• Scrap metal being recycled (see WAC 173-303-071).

If you follow the requirements for recycling the wastes listed below, they are excluded from all other dangerous waste requirements:

• Some refrigerants
• Some wastes burned for energy recovery
• Spent antifreeze
• Spent lead-acid batteries
• Used oil
• Universal waste
• Waste containing precious metals

Learn more about recycling requirements for state-only dangerous waste.

F waste codes are the most common. They include:

• Solvents, like trichloroethylene, toluene, and others that have been used to clean or dissolve something.
• Several process wastes, like those generated from cyanide-based electroplating.

K waste codes include wastes from specific industries or processes described on the K-list, such as:

• Wastewater sludges from treatment processes or distillation bottoms.
• Industries like pulp and paper mills, wood preservation, iron and steel production.

P and U waste codes are uncommon and mainly come from labs or medical facilities. They are used for discarded chemical products — unused, commercial products that become waste and contain only one active ingredient.

• Wastes with P codes are toxic and more acutely hazardous than those with U codes. They are more stringently regulated with a quantity exclusion limit (QEL) of 2.2 pounds.
• Wastes with U codes are regulated like other dangerous wastes with a QEL of 220 pounds.

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 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. Corrosive wastes have a D002 code.

A waste is corrosive if it meets either of these conditions:

• Water-based with a pH of less than or equal to 2 (acidic) or greater than or equal to 12.5 (basic).
• Liquid waste that corrodes steel at a rate greater than 0.25 inches per year (use EPA’s SW-846 Test Method 1110A to determine).

Solid corrosives are also a Washington state-only waste with the waste code WSC2.

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.

Examples include:

• Lithium batteries
• Explosives

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.

Examples include:

• Heavy metals
• Pesticides
• 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.

Washington state uses the term "dangerous waste" rather than the federal term of "hazardous waste." This is because Washington state's Dangerous Waste Regulations are more protective than federal laws. The definition of "dangerous waste" is more expansive than "hazardous waste."

Waste codes are four-character codes that describe the type of waste and the risks it represents. A dangerous waste might have multiple codes. All applicable codes must be assigned. For example:

• D001: Ignitable
• D008: Tests for lead
• D039: Tests for tetrachloroethylene (also called perchloroethylene, or PERC)
• WT01: Washington state-only toxic waste

Designation will help you identify waste codes.

Many businesses hire a hazardous waste service provider to transport and dispose of their dangerous waste. Some service providers can help designate waste and provide waste labels with applicable waste codes.

However, businesses remain fully responsible for:

• Accurate waste designation.
• Knowing what rules apply to their site.
• All waste they generate, even after it’s disposed of by a hazardous waste service provider.