Determination of the quantity of combustible material in cable products in the process of fire safety testing

Abstract

In order to protect objects from dangerous manifestations of fire of cable products, electrical lines are designed and projected in accordance with the fire-protection requirements and the normative documents. Purpose. The purpose of this article is to analyze this problem in several areas concerning the situation with a systematic approach to the technical regulation in Ukraine of such a sector of fire safety as the requirements for cable-wiring lines. Methods. Methods of research: calculations using a mathematical model; comparison of the results of the calculation, forecasting of the boundary parameters of the technical condition and monitoring of the cable material properties; examination, qualification, definition of indicators of fire safety of cables and wires in the composition of the electrical grids of buildings, structures, foundations and metal structures, taking into account laying conditions. Different methods for volume and mass calculating, fire tests of electrical and fiber optic cables were applicated. Tests of vertically arranged wires or cables laid in beams on the vertical propagation of the flame (Category A F / R, Category A, Category B) were conducted. Results. The experimental study of the installation parameters test and indicators of fire safety for cable-wiring products in their vertical laying that reduce the overall fire safety level of facility electric power operation were conducted. Critical analysis of the current state of development was done. The basis of the fire safety requirements for standardization of cable lines were formulated. The measures for testing methods implementation with description of these methods were proposed. Conclusion. Determination of the combustible material quantity by volume and by mass is not regulated in the current normative documents on fire safety, although this criterion is often used precisely when establishing requirements for fire safety: to buildings, cable installations, to the installation of fire automatics systems and to others. A method for calculating the volume of combustible material for determining the fire risk of cable-conductive products is proposed. The method can be used during designing of wiring lines and during their exploitation. Experimental researches of fire hazard indicators of cable-wiring products were conducted; their group of flame distribution was installed. The method of determining the quantity of combustible material by volume, by mass and with testing of mass loss of combustible material was applied.