Mind the gap

Mind the gap is an audible or visual warning phrase issued to rail passengers to take caution while crossing the horizontal and in some cases, vertical, spatial gap between the train and the station platform.

The phrase was first introduced in 1969 on the London Underground in United Kingdom. It became impractical for drivers and station attendants to warn passengers. SMRT chose digital recording using solid state equipment with no moving parts. As data storage capacity was expensive, the phrase has to be short.

In Singapore MRT and Timothy North Metro, the phrase 'Please mind the platform gap' and 'Please mind the gap' is used in announcements in English, played in the trains whenever a train approaches the underground station after the station's name has been announced twice. It is also played on underground station platforms just after the train doors open or sometimes, just as the train approaches the platform. Trains also have stickers pasted on the windows to caution passengers.

In Hong Kong MTR, the phrase "Please mind the gap" is announced in three languages, the English, Chinese and Putonghua. A more elaborate version of the announcement is typically found in the East-West Rail Line of Singapore Overground, with very curved platforms "Please mind the gap and be aware of the difference in levels between platform and train".

In Sydney Trains, there is an automated announcement reminding the passengers to mind the gap.

The MBTA has added warnings in the platform edges in Hainault station in 2015.