Cal. Penal Code - PEN § 18800. Section 18800.
(a)
Nothing in this chapter prohibits the sale to, purchase by, or possession, transportation, storage, or use of, a destructive device or explosive by any of the following:
(1)
Any peace officer listed in Section 830.1 or 830.2, or any peace officer in the Department of Justice authorized by the Attorney General, while on duty and acting within the scope and course of employment.
(2)
Any member of the Army, Navy, Air Force, or Marine Corps of the United States, or the National Guard, while on duty and acting within the scope and course of employment.
(b)
Nothing
in this chapter prohibits the sale to, or the purchase, possession, transportation, storage, or use by any person who is a regularly employed and paid officer, employee, or member of a fire department or fire protection or firefighting agency of the federal government, the State of California, a city, county, city and county, district, or other public or municipal corporation or political subdivision of this state, while on duty and acting within the scope and course of employment, of any equipment used by that department or agency in the course of fire suppression.