Where does a speed zone boundary change?

Navigating speed zones

When approaching a speed limit change along the highway, as indicated by appropriate signage, where is the actual speed zone boundary? Am I expected to change my speed once the sign becomes visible to me so I have reached the new limit by the time I reach the sign? Or, do I maintain my speed and then increase or reduce it only after I have reached the sign?

Imagine a line painted across the highway perpendicular to the edge of the road at the sign. Before you reach that line, you must follow the limit in the zone you are in. Once you have passed the line, you must travel at (or below) the speed of the zone that you have entered.

Although many drivers think as soon as they are able to see and read the sign it is an indication they are allowed to speed up, they are not correct. You must pass the sign before speeding up.

The reverse is true though, when you see the sign calling for a reduction in speed. It is wise to begin slowing so you are travelling at the correct speed before you pass the sign. In fact, there are signs posted to remind you of that.

Drivers typically speed up as soon as they can see the sign and begin to slow after they pass it. That behaviour often creates problems for other road users.

One example is when a reduced speed zone is necessary to allow traffic from side roads to join the major traffic flow. Failing to drive at the reduced speed puts both the driver entering the highway and the driver that failed to slow for them at increased risk for a collision.

This article is written by or on behalf of an outsourced columnist and does not necessarily reflect the views of Castanet.

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About the Author

Tim Schewe is a retired constable with many years of traffic law enforcement experience. He has been writing his column for most of the 20 years of his service in the RCMP.

The column was 'The Beat Goes On' in Fort St. John, 'Traffic Tips' in the South Okanagan and now 'Behind the Wheel' on Vancouver Island and here on Castanet.net.

Schewe retired from the force in January of 2006, but the column has become a habit, and continues.

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The views expressed are strictly those of the author and not necessarily those of Castanet. Castanet does not warrant the contents.

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