SN EN 16704-2-1:2017

This European Standard defines minimum functional and non-functional requirements for developing a Track Warning Systems (TWS) to warn persons during their work on or nearby the track about the approaching of trains or rail vehicles using acoustical and visual TWS-Signals. These systems may also be able to influence the approaching of trains and rail vehicles by stoppage function.This European Standard is applicable:- to systems, sub-systems and components within TWS, including those containing software; in particular;- to new TWS;- to new integrations of systems, sub-systems and components into existing TWS;- to modifications of TWS developed according to this standard.For single warning units (e.g. simple electrical horns) it is recommended to use this standard, too.This document does not deal with:- hazards during the installation of the TWS caused by trains or rail vehicles on the lines;- hazards caused by the improper use of TWS;- hazards caused by the improper behaviour of persons working on or nearby the track;- CO2-tyfone, human operated pressure signal horns, flags, detonators or machine warning systems according to UIC 644;- national safety regulations to plan and operate TWS in track.