Cal. Penal Code § 2933.3

(a) Notwithstanding any other law, any inmate assigned to a conservation camp by the Department of Corrections and Rehabilitation, who is eligible to earn one day of credit for every one day of incarceration pursuant to Section 2933 shall instead earn two days of credit for every one day of service. The enhanced credit authorized pursuant to this subdivision shall only apply to those prisoners eligible after January 1, 2003. (b) Notwithstanding any other law, any inmate who has completed training for assignment to a conservation camp or to a correctional institution as an inmate firefighter or who is assigned to a correctional institution as an inmate firefighter and who is eligible to earn one day of credit for every one day of incarceration pursuant to Section 2933 shall instead earn two days of credit for every one day served in that assignment or after completing that training. (c) In addition to credits granted pursuant to subdivision (a) or (b), inmates who have successfully completed training for firefighter assignments shall receive a credit reduction from his or her term of confinement pursuant to regulations adopted by the secretary. (d) The credits authorized in subdivisions (b) and (c) shall only apply to inmates who are eligible after July 1, 2009.