Determining minimum sightlines at grade crossings

Sightline requirements vary depending on the safety attributes at the grade crossing: Note: If the road design speed or the railway design speed varies on • Public or Private grade crossing with a Warning System with either side of the grade crossing, you must make stand-alone Gates: sightline requirements do not apply but the warning calculations for each quadrant. [...] Factor 2: Road Crossing Design Speed Factor 1: Design vehicle and its dimensions The ‘road crossing design speed’ is the motor vehicle speed that corresponds to the grade crossing’s current design: A ‘design vehicle’ is the most restrictive vehicle that authorities expect • The road authority chooses the road crossing design speed for to regularly use the grade crossing: public grade crossings. [...] The SSD is based on the road crossing design speed: • Use Table 2 to determine the SSD for Passenger Car Class • Use Table 3 to determine the SSD for Truck Class. [...] The following process to calculate sightlines in accordance with the Grade Crossings Regulations applies to all grade crossings: 2.2.1 Determining Sightlines from the SSD Approach Point • new or existing, • public or private, The SSD is the minimum sight distance along the road approach that • after or before 7 years, a crossing user needs to react to approaching railway equipment. [...] DSSD is equal to the distance the design vehicle must go from the SSD point completely past the clearance point on the other side of the grade crossing, at its road crossing design speed.