Stopping distance (safety distance)
How far a hazard keeps moving after a stop is demanded; for fixed machines it drives the minimum distance between a safeguard and the hazard.
The network analogy
A bandwidth-delay product for motion. Speed multiplied by reaction time gives the distance covered before anything happens.
Why it matters for wireless
Every millisecond the network adds to the stop chain becomes distance once it is multiplied by a speed, so a longer connection timeout chosen to survive roaming can increase the required safety distance.
Machinery rules express this as speed multiplied by time. US rules for mechanical power presses use Ds = 63 inches per second x Ts1, with Ts the press stopping time. ISO 13855, as applied in a vendor application note, uses S = (K x T) + C, with K an approach speed of 1600 mm per second2 and T the overall stopping performance, and that note counts the network connection delay inside T.
A moving vehicle covers distance at its own travel speed for the whole time it takes to detect a problem and begin stopping, then more while braking. Those values belong to the vehicle maker and the risk assessment. The network contributes the delay before the stop begins.
About this page
Built from 2 sources: 1 regulator or government source and 1 vendor document. Researched and drafted with AI assistance, then reviewed and approved by Ben Rutter on . How pages are made
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Cite this page
Plain
Ben Rutter. "Stopping distance (safety distance)." OT Wireless, published October 5, 2026. https://otwireless.com/glossary/stopping-distance/
APA 7
Rutter, B. (2026, October 5). Stopping distance (safety distance). OT Wireless. https://otwireless.com/glossary/stopping-distance/
BibTeX
@misc{rutter2026stoppingdistance,
author = {Rutter, Ben},
title = {{Stopping distance (safety distance)}},
year = {2026},
howpublished = {\url{https://otwireless.com/glossary/stopping-distance/}},
organization = {OT Wireless},
}