Cal. Code Regs. tit. 8, § 1605.18 – Electric Motors.

(a) Motor installations shall be made in accordance with provisions of applicable local codes and the Electrical Safety Orders.
(b) Only enclosed switches with grounded cases and fuses or circuit breakers shall be used.
(c) Control panels shall be enclosed and unauthorized persons shall not be permitted access to such panels.
(d) An emergency means shall be provided within reach of the operator to cutoff the electric power.