Section 39.303. Protection against induced voltages

Telephone or other signaling equipment which is necessarily handled by persons and which is connected to a line that parallels a supply circuit in such manner that by reason of exposure to the supply circuit under normal operating conditions more than 150 volts are induced between the terminals of the signaling equipment and ground shall be protected by one or more of the following means:

(1) Exposed metal parts of the equipment shall be insulated from the circuit, and the circuit shall be protected by arresters having a breakdown potential not exceeding 1/2 the insulation between the above named noncurrent-carrying metal parts and the current-carrying parts.

(2) Cords shall have an additional insulating tubing protection.

(3) Exposed noncurrent-carrying metal parts shall be permanently grounded and current-carrying metal parts shall either be permanently grounded or adequately shielded. Reference should be made to § 39.302 (relating to guarding current-carrying parts).

(4) Equipment shall be so located that persons coming into contact with the equipment shall be obliged to stand either on an insulated platform or in a booth of suitable insulating material.

Notation

Cross References

This section cited in 34 Pa. Code § 39.192 (relating to scope).