Public Utilities Code § 16195

Examinations shall be practical, and shall relate to those matters only which will fairly test the relative capacity of the persons examined to discharge the duties of the positions which they seek, and shall include, when appropriate, tests of manual or professional skill. The selection of laborers shall be governed by priority of application as far as practicable. No question in any examination shall relate to political or religious opinions or affiliations. The board shall control all examinations.