Automatische TreinBeïnvloeding or ATB is a Dutch system of Automatic Train Protection developed in the 1950s.

Its installation was spurred by the Harmelen train disaster of 1962.

ATB operates by the train collecting electrical signals from line-side apparatus which will overide the driver's controls in the following situations:

• a) failure to brake for a red signal (ATB makes an immediate brake application)
• b) failure to reduce speed at a caution signal (ATB will slow the train sufficiently to stop at the next signal)
• c) failure to observe speed limit (ATB slows the train) (such as around a sharp curve or low speed turnout)

For completeness, the ATB should also:

• d) restrict the speed of the train after passing a signal at danger. This was a factor in the Glenbrook train disaster.

See also

• Train stop – protects against a)
• Automatic Warning System – protects against b)
• Automatic train protection – protects against c)