Editing Railway platform (section)

=== Curvature ===
{{See also|Platform gap|Platform gap filler}}
Ideally platforms should be straight or slightly [[convex curve|convex]], so that the guard (if any) can see the whole train when preparing to close the doors. Platforms that have great curvature have blind spots that create a safety hazard. Mirrors or [[Closed-circuit television|closed-circuit camera]]s may be used in these cases to view the whole platform. Also passenger carriages are straight, so doors will not always open directly onto a curved platform &ndash; often a [[platform gap]] is present. Usually such platforms will have warning signs, possibly auditory, such as [[London Underground]]'s famous phrase "[[Mind the gap]]".

There may be moveable [[Platform gap filler|gap filler]] sections within the platform, extending once the train has stopped and retracting after the doors have closed. The [[New York City Subway]] employs these at [[14th Street–Union Square (IRT Lexington Avenue Line)|14th Street–Union Square]] on the [[IRT Lexington Avenue Line]] and at [[Times Square (IRT 42nd Street Shuttle)|Times Square]] on the [[42nd Street Shuttle]], and formerly at the [[South Ferry loops (New York City Subway)|South Ferry]] outer loop station on the [[IRT Broadway–Seventh Avenue Line]].