Pset_RailwaySignalSighting Properties that define information about signal sighting or visibility in railways. These properties are applicable to occurrences of _IfcSignal_ and _IfcSign_. IfcSignal IfcSign IfcSignal,IfcSign SignalSightingAchievableDistance Reading distance of the signal, which is achievable with the help of mitigation works. SignalSightingAvailableDistance Reading distance of the signal without having any mitigation works. SignalSightingCombinedWithRepeater Combined reading distance for the signal and any associated repeaters. SignalSightingMinimum Minimal distance in which the signal has to be readable. SignalSightingPreferred Preferred distance in which the signal shall be readable. SignalSightingRouteIndicator Required reading distance for the route indicator. SignalViewingMinimumInFront Smallest distance where the signal has to be readable (for train very close to the signal).