Government Code § 31739.33

(a) Except as provided in subdivision (b), a retirement allowance, optional death allowance, or annual death allowance, including an allowance payable to a survivor of a member, payable to or on account of any member of this system or of a superseded system who has been or was retired for disability which did not on July 1, 1976, exceed five hundred dollars ($500) per month is hereby increased as follows:

(b) No allowance shall be increased to more than five hundred dollars ($500) per month pursuant to subdivision (a).

This section shall not be operative in a county until such time as the board of supervisors shall, by resolution adopted by majority vote, make the provisions of this section applicable in that county.