Fireworks laws in California

All fireworks, including safe and sane ones, are illegal in the City.
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Here in Los Angeles, the LAMC explicitly prohibits all fireworks within City limits.
LAMC Section 57.5608.1.2 states as follows:
It shall be unlawful for any person to use, give, possess, sell,
or discharge any fireworks in the City of Los Angeles.
Although fireworks are considered illegal for personal possession or use in the
City, exceptions have been made to allow for specified fireworks shows (i.e. “displays”)
so long as the shows are permitted by the Los Angeles Fire Department (LAFD) and are
conducted in conformance with state law.

SFPD and SFFD 4th of July Fireworks Safety Information
June 30, 2016 | 11:21 AM
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As the 4 th of July celebratory events are upon us, the San Francisco Police and Fire Departments are reminding all residents and visitors that San Francisco has a zero tolerance for the use and sale of all fireworks.
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Possession of fireworks such as sky rockets, bottle rockets, roman candles, aerial shells, firecrackers and other types that explode, go into the air, or move on the ground in an uncontrollable manner can lead to a possible fine or jail time in the county jail. Even “Safe and Sane” Fireworks, such as firecrackers and sparklers, are considered illegal.
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SFPD emphasizes that fireworks are illegal in San Francisco and police will be enforcing fireworks possession and sales laws.

Division 1.4 consists of explosives that present a minor blast hazard. Examples are common fireworks, toy caps, empty primed grenades, and some small arms ammunition.
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341.2 Mailability, Packaging, and Marking
Explosives are generally prohibited from being mailed under 18 U.S.C. § 1716. The following conditions apply for mailing Hazard Class 1 items:
International Mail : All explosives are prohibited.
Domestic Mail via Air Transportation: All explosives are prohibited.
Domestic Mail via Surface Transportation: Generally, explosives are prohibited, with exceptions for Division 1.4S toy propellant devices and safety fuses that have been approved by the director, Product Classification before mailing (refer to 214 for contact information). A shipping paper is required.

UPS Prohibited Items
Examples of items prohibited by UPS include, but are not limited to the following:
Shipments prohibited by law
Bank bills, notes or currency
Common fireworks

We do not accept for delivery:
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Fireworks
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FedEx accepts certain classes and divisions of hazardous materials for transport. Before you ship, please refer to the following list to ensure your packages contain only accepted hazardous materials.
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1.4 1
Explosives
1.4/Explosive 1.4
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1 Except fireworks.

§ 1500.17 Banned hazardous substances.
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(3) Fireworks devices intended to produce audible effects (including but not limited to cherry bombs, M-80 salutes, silver salutes, and other large firecrackers, aerial bombs, and other fireworks designed to produce audible effects, and including kits and components intended to produce such fireworks) if the audible effect is produced by a charge of more than 2 grains of pyrotechnic composition; except that this provision shall not apply to such fireworks devices if all of the following conditions are met:
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(8) Firecrackers designed to produce audible effects, if the audible effect is produced by a charge of more than 50 milligrams (.772 grains) of pyrotechnic composition (not including firecrackers included as components of a rocket), aerial bombs, and devices that may be confused with candy or other foods, such as “dragon eggs,” and “cracker balls” (also known as “ball-type caps”), and including kits and components intended to produce such fireworks except such devices which meet all of the following conditions:
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(9) All fireworks devices, other than firecrackers, including kits and components intended to produce such fireworks, not otherwise banned under the act, that do not comply with the applicable requirements of part 1507 of this chapter, except fireworks devices which meet all the following conditions: