(a) The functioning of an electric contact to prevent the movement of the car shall not be dependent upon the closing of an electric circuit.

(b) Electric contacts shall be designed so that they are directly opened by a lever or other device attached to and operated by the door or gate. Contacts employing springs, gravity or a combination of the two forces, may be used when approved by the Industrial Commissioner if the device is found to be safe, practical and reliable. These forces, however, are not considered desirable if they are arranged so that their failure would create an unsafe condition.

(c) The force or forces employed to open the contact shall be such that even without lubrication of the mechanism the intended functioning of the electric contact shall be completely performed.

(d) Contacts shall be so designed and installed as to prevent, so far as possible, being tampered with or intentionally rendered inoperative (except as noted in § 8-1.57 covering emergency release). (See also §§ 8-1.6, 8-1.58, 8-1.59.)