Hazardous Substances

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Regulatory Compliance

CVMA Guide to Cal/
OSHA Compliance

Hazardous Substances

Hazardous waste is a waste with properties that make it potentially dangerous or harmful to human health or the environment. Hazardous wastes can be liquids, solids, or contained gases. It is important to note that from a legal standpoint, such items do not become “waste” until someone no longer has use for them, or until they are discarded. Discarded hazardous items refer to those which are disposed of, stored or accumulated, recycled under certain circumstances, or treated to be neutralized into an inert state. Additionally, any hazardous item that is mislabeled or inadequately labeled is considered to be discarded, unless the label is corrected within 10 days. If a container containing a hazardous item is deteriorated or damaged, it is considered discarded unless the hazardous item is repackaged within 96 hours.

The California Environmental Protection Agency Department of Toxic Substances Control (Cal/EPA DTSC) has jurisdictional authority over hazardous waste. They may inspect premises, subpoena records, interview staff, and file charges in both administrative and criminal court for those who are suspected of violating hazardous waste laws.

In general, the following criteria can be applied to help determine if a waste is considered hazardous:

ClassificationDefinitionExampleLegal Reference
Is it Ignitable?In liquid form has a flash point of less than 60 degrees Centigrade; in solid form can ignite at room temperature through friction or absorption of moisture; or is an ignitable compressed gas.Anesthetic gasesCCR Title 22 Section 66261.21
Is it Corrosive?In liquid form, will have a pH of less than 2 or greater than 12.5Strong acids or basesCCR Title 22, Section 66261.22
Is it Reactive?Can explode, become unstable, release a toxic gas, or undergo violent reaction when mixed with water or when exposed to heat.Ethylene OxideEtherCCR Title 22 Section 66261.23
Is it Toxic?Displays characteristics of toxicity in the environment or can be harmful to health at or above referenced levels.

Powdered copper, zinc and selenium (used in oral boluses for livestock)Mercury




Fluorescent light bulbs


Difquik Stain

CCR Title 22 Section 66261.24

Cal EPA offers a free online education module to help generators determine what constitutes hazardous waste. It can be found at: Training Opportunities | CalEPA

Cal EPA DTSC can be reached at:

1001 I Street
Sacramento, CA 95814-2828

Mailing Address:
P.O. Box 806
Sacramento, CA 95812-0806

A list of regional offices can be found here.

Hazardous Waste FAQ

Hazardous Waste 411

Cal EPA Agency Profile