Cal. Labor Code § 6500

(a) For those employments or places of employment that by their nature involve a substantial risk of injury, the division shall require the issuance of a permit prior to the initiation of any practices, work, method, operation, or process of employment. The permit requirement of this section is limited to employment or places of employment that are any of the following: (1) Construction of trenches or excavations that are five feet or deeper and into which a person is required to descend. (2) The construction of any building, structure, falsework, or scaffolding more than three stories high or the equivalent height. (3) The demolition of any building, structure, falsework, or scaffold more than three stories high or the equivalent height. (4) The underground use of diesel engines in work in mines and tunnels. This subdivision does not apply to motion picture, television, or theater stages or sets, including, but not limited to, scenery, props, backdrops, flats, greenbeds, and grids. (b) On or after January 1, 2000, this subdivision shall apply to motion picture, television, or theater stages or sets, if there has occurred within any one prior calendar year in any combination at separate locations three serious injuries, fatalities, or serious violations related to the construction or demolition of sets more than 36 feet in height for the motion picture, television, and theatrical production industry. An annual permit shall be required for employers who construct or dismantle motion picture, television, or theater stages or sets that are more than three stories or the equivalent height. A single permit shall be required under this subdivision for each employer, regardless of the number of locations where the stages or sets are located. An employer with a currently valid annual permit issued under this subdivision shall not be required to provide notice to the division prior to commencement of any work activity authorized by the permit. The division may adopt procedures to permit employers to renew by mail the permits issued under this subdivision. For purposes of this subdivision, “motion picture, television, or theater stages or sets” include, but are not limited to, scenery, props, backdrops, flats, greenbeds, and grids.