ITU-T Recommendations

This Recommendation gives the basic requirements to be met by gas discharge tubes for the protection of exchange equipment, telecommunication lines and subscribers' or customer equipment from overvoltages. It is intended to be used for the harmonization of existing or future specifications issued by gas discharge tube manufacturers, telecommunication equipment manufacturers or Administrations.Only the minimum requirements are specified for essential characteristics. As some users may be exposed to different environments or have different operating conditions, service objectives or economic constraints, these requirements may be modified or further requirements may be added to adapt them to local conditions.This Recommendation provides guidance on the use of gas discharge tubes to limit overvoltages on telecommunications lines.