scope:

Telephony services delivered via an antenna installation may be subjected to lightning discharges. This Recommendation provides requirements to minimize the risk of injury to users of the service and damage to equipment. It provides requirements to achieve protection of telecommunications and video content antenna systems, including satellite antennas, against lightning discharges and mains contact including contact with aerial power service leads

When protection against direct lightning discharges is not required, this Recommendation requires protection against mains contact to minimize the risk of injury to users of the service and to network operator personnel.

When protection against direct lightning discharges is required, this Recommendation defines protection measures distinguishing two cases:

1) The antenna is located on the building.

2) The antenna is installed on a mast near to the building at a maximum distance of about ten metres.

This Recommendation does not provide methods to protect the antenna and associated cabling against a direct strike to the antenna mast (see clause 7.2).

Damage to equipment is minimized by providing requirements to achieve protection against lightning.

This Recommendation provides requirements for:

- the resistibility of the equipment;

- how and when to protect the customer's premises from direct strikes;

- how and when to bond the mast or tower to the customer building electrical installation earthing system;

- how and when to protect the services, i.e., the power supply for the service, the telecommunication line and the antenna cable, entering the customer's building.

This Recommendation does not apply to structures where there is the risk of explosion, nor to hospitals with life-saving electrical equipment or structures where failures of internal systems immediately endanger human life.

This Recommendation covers the protection of antennas installed at private buildings ranging in size from small single-storey buildings up to multi-storey buildings. This Recommendation only applies in the case when the antenna is being installed to supply service to the building on which the antenna is being installed. For radio base station installations refer to [ITU-T K.56].