Selective Door Operation

Selective Door Operation, also called Selective Door Opening (or SDO) is a mechanism employed primarily on trains (although buses with multiple doors also generally have this feature) that allows the Driver or Conductor/Guard to open the doors of a train separately.

Read more about Selective Door Operation:  Purpose and Operation of SDO, See Also

Famous quotes containing the words selective, door and/or operation:

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    Blake Morrison (b. 1950)

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    Annie Dillard (b. 1945)

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    Sydney Smith (1771–1845)