Cal. RTC § 213.7

(a) As used in Section 214, “property used exclusively for religious, hospital, scientific or charitable purposes” shall include the property of a volunteer fire department that is used exclusively for volunteer fire department purposes, provided that the department qualifies for exemption either under Section 23701d or 23701f of this code or under Section 501(c)(3) or 501(c)(4) of the Internal Revenue Code. This section shall not be construed to enlarge the “welfare exemption” to apply to organizations qualified under Section 501(c)(3) or 501(c)(4) of the Internal Revenue Code, but not otherwise qualified for the “welfare exemption” under other provisions of this code.

(b) As used in this section, “volunteer fire department” means any fund, foundation or corporation regularly organized for volunteer fire department purposes, that qualified as an exempt organization on or before January 1, 1969, either under Section 23701d or 23701f of this code or under Section 501(c)(3) or 501(c)(4) of the Internal Revenue Code, having official recognition and full or partial support of the government of the county, city, or district in which the volunteer fire department is located, and that has functions having an exclusive connection with the prevention and extinguishing of fires within the area of the county, city, or district extending official recognition for the benefit of the public generally and to lessen the burdens of the entity of government which would otherwise be obligated to furnish such fire protection.

(c) For purposes of subdivision (a), an organization shall not be deemed to be qualified as an exempt organization unless the organization files with the assessor a valid organizational clearance certificate issued pursuant to Section 254.6.