Chapter 70 ELECTRICITY.
Section 70-42 MASTS, ANTENNAS AND TRANSMISSION LINES.
The provisions of this section shall apply to masts and antennas and to transmission
A. Masts or antennas shall be of noncombustible and noncorrosive material, except
that in the
case of ground support, a wooden pole may be used when adequately treated with a wood
preservative. When a mast or antenna is installed on a roof, it shall be mounted on its own
platform and be securely anchored with guy wires.
B. Outdoor antennas shall be of an approved type and shall not exceed the maximum
fifty (50) feet above a roof support or seventy (70) feet above ground support. In areas where
reception may be affected by the obstruction of tall buildings, antennas in excess of the above
specified height may be installed only when approved by the Electrical Inspector. Every antenna
shall be adequately grounded for protection against lightning. In no case shall an antenna be
installed nearer to a street or sidewalk than the height of the antenna plus one (1) foot, unless
approved by the Electrical Inspector. Anchor points for antennas, masts and guy wires shall be
anchor screws or lead expansion shields drilled into solid block, concrete or other
noncombustible construction. No wires, cables or guys shall cross or extend over any part of a
public street, way or sidewalk.
C. Transmission lines shall be kept at least twelve (12) inches from existing telephone
wires. Rawl plugs are approved only for supporting transmission lines. Standoff support
insulators must be used at least every ten (10) feet in running the transmission line down the
D. Lightning arrestors shall be approved by the Underwriters' Laboratories, Inc.,
and both sides
of the line shall be adequately protected with proper arrestors or neon lamps to remove static
charges accumulated on the line. When lead-in conductors of polyethylene ribbon type are used,
lightning arrestors shall be installed in each conductor. If a coaxial cable is used for the lead-in,
suitable protection may be provided without lightning arrestors by grounding the exterior metal
E. Antennas shall be designed and installed in such manner as to resist a wind pressure
twenty-five (25) pounds per square foot, and in no case shall guy wires be less than three-thirty-seconds-inch
five-strand cable or equivalent, galvanized. Rawl plugs shall be used for guy wires
or for mounting brackets.
F. Ground wires shall be of copper wire, not smaller than No. 10 for grounding masts
lightning arrestors, and shall be installed in a mechanical manner with as few bends as possible,
maintaining a clearance of a least two (2) inches from the combustible material.
G. Ground straps for grounding masts and attaching arrestors to water pipe shall
H. Miscellaneous hardware, such as brackets, turnbuckles, thimbles, clips, etc.,
shall be hot-dipped galvanized or similarly treated for weather protection. The turnbuckles shall
against turning by threading the guy wires through the turnbuckles.