Cal. Health & Safety Code § 34312.4
(a) Subject to the requirements of Article 5 (commencing with Section 34350), for purposes of implementing a home financing program an authority has the following powers and duties:
(3) To establish, by rules or regulations, in resolutions relating to any issuance of bonds or in any documents relating to the issuance, standards, and requirements applicable to the purchase of home mortgages or the making of loans to lending institutions the authority deems necessary or desirable to effectuate the purposes of this section, which may include without limitation any of the following:
(c) Each authority which finances housing pursuant to this section shall adopt regulations establishing criteria for the qualification of persons and families, which may differ among different areas of operation of authorities to reflect varying economic and housing conditions. In developing this criteria, factors similar to the following shall be taken into consideration:
(d) Criteria for qualification of persons and families pursuant to this section shall include a maximum household income, which maximum shall not exceed the following:
(3) One hundred fifty percent of the median household income for mortgages made for improving a home or for homes where the purchaser will be the first occupant in any city, the entire area of which, or in any county in which a portion of the county, is designated by the United States Department of Commerce, Economic Development Administration as a special impact area within a Title IV redevelopment area, pursuant to Section 401 of the federal Public Works and Economic Development Act of 1965, as amended, and which is eligible for Urban Development Action Grant funds under the current distress standards established for cities and counties by the Secretary of the United States Department of Housing and Urban Development pursuant to Section 119 of the Housing and Community Development Act of 1974, if the homes purchased or improved are situated within the boundaries of a special impact area as defined by the Economic Development Administration, and that designation is in effect on the date of sale of revenue bonds issued under this section.
As used in this subdivision, “median household income” means the highest of (A) statewide median household income, (B) countywide median household income, or (C) median family income for area as determined by the United States Department of Housing and Urban Development, with respect to either a standard metropolitan statistical area or an area outside of a standard metropolitan statistical area.