Four Characteristics of Hazardous Waste for Completing Waste Profiles

All hazardous waste shipments must be accompanied by a waste profile that provides critical information about the material being shipped. To complete a hazardous waste profile, you must understand what defines hazardous waste. These four characteristics make up hazardous waste.


Corrosive substances destroy other substances with which they come into contact, posing immediate threat. For example, they can eat through containers, causing hazardous waste leaks. Corrosive materials that require special handling include nitric acid and hydrochloric acid. To be corrosive, liquids must have a pH of 2 or less, greater than or equal to 12.5, or be able to corrode steel.


Oxidized and compressed gases are ignitable, as are solids that spontaneously combust and liquids with a flash point. Flash point refers to the lowest temperature at which waste fumes will ignite, which is 60 degrees Celsius (140 degrees Fahrenheit).


Reactive wastes pose an immediate threat. They are especially dangerous because they are unstable, thus likely to react with improper handling. Too many materials are reactive to generate a simple definition. Generators should identify any unstable materials that experience violent change or materials that become reactive when mixed with water. For example, materials are considered hazardous if toxic gases are released when the material is mixed with water.


Toxic materials pose a threat to groundwater, as leaks can contaminate the water supply, causing long-term effects on health and the environment. The EPA has a list of 60 contaminants, so generators can use the list to check for materials toxicity.

By understanding how these components pose a threat to human health and the environment, and knowing what makes a material toxic, reactive, ignitable, or corrosive, you can ensure all hazardous waste is properly marked for shipping or disposal.