FIRE SAFETY REQUIREMENTS FOR CABLE NETWORKS OF FIRE PROTECTION SYSTEMS OF NUCLEAR POWER PLANTS

Проанализированы основные нормативные документы, содержащие требования пожарной безопасности, предъявляемые к электрооборудованию атомных электростанций (АЭС), включая кабельные линии и электропроводки систем противопожарной защиты. Рассмотрены правила и номенклатура для выбора типа исполнения кабельных изделий на этапах проектирования АЭС и в процессе эксплуатации электросетей. Изложены результаты огневых крупномасштабных испытаний кабельного потока, состоящего из не распространяющих горение кабелей различного типа исполнения, проведенных в соответствии с разработанной методикой в кабельном сооружении. Даны рекомендации по повышению эффективности использования в кабельном туннеле огнестойких плит в качестве мер пожарной профилактики. There was carried out analysis of the main documents regulating fire safety requirements for NPP cable networks, including SDR systems. Knowledge and strict compliance with the norms governing the nomenclature of cable products when choosing and using them at the design and operation stages of these facilities are of great importance for the prevention of fires associated with the ignition of cables at nuclear power plants. There are given clarifications on the important issue discussed in the norms on the need to use flame retardants (paints) applied to streams of non-flammable cables with a combustible load of more than 0.007 m3 per linear meter of the line. Comments are given on the regulatory and technical documents under consideration. Large-scale fire tests of group cable lines and electrical wiring in a cable tunnel were carried out, which showed the possibility of ignition and propagation of fire along a horizontal cable stream from a real and energetically justified ignition source, in order to verify and substantiate the regulatory requirements being developed. A positive assessment of the results of the experiment as a whole was given, since the permissible limit for the spread of combustion of group cable laying provided by the methodology was not exceeded, which in turn showed the expediency and obvious preventive necessity of using fire-resistant plates (ACEED, PROMAT, etc.) during installation of the cable laying line, which significantly reduce the scale and speed of combustion propagation along cable flows. Based on the research carried out, there are given recommendations to improve the efficiency of using ACEED plates by modernizing their shape and dimensions.