This standard: ¾ defines the various profiles needed to install, verify and maintain the various structures near the structure gauge; - lists the various phenomena to be taken into account to determine the structure gauge; - defines a methodology that may be used to calculate the various profiles from these phenomena; - lists the rules to determine the distance between the track centres; - lists the rules to be complied with when building the platforms; - lists the rules to determine the pantograph gauge; - lists the formulae needed to calculate the structure gauges in the catalogue.