Pesticide registrations - what types are available?
Section 3 - Also known as the initial pesticide label registration; contains basic registered uses, use directions, requirements, and prohibitions.
Section 18 - Also known as an emergency exemption from registration; Section 18 of FIFRA authorizes the U.S. EPA to allow an unregistered use of a pesticide for a limited time if the EPA determines that emergency conditions exist. What is an emergency condition? This is defined as an 'urgent, non-routine situation that requires the use of a pesticide.' States must petition the U.S. EPA to issue a section 18 exemption. There must be no feasible alternatives.
For more information, see: https://www.cdpr.ca.gov/docs/registration/guides/section18.pdf
Section 24c - Also known as a special local need registrations; FIFRA section 24 grants states pesticide regulatory authority. One that is commonly encountered is the 24c; 24c gives states the authority to issue a use registration for a federally registered pesticide. This allows individual states to expand the uses of certain registered pesticides within their jurisdictions.
For more information, see: https://www.cdpr.ca.gov/docs/registration/guides/section24c.pdf