View Desktop

Low ramp speeds an open invitation for tailgating?

Published July 17, 2012
13

Comments

Q: How do officials decide on highway ramp “advisory” speeds? Many on-ramp and transfer-ramp speeds seem excessively low to me. I find that going only 10 km/h over the posted ramp speeds earns me a lot of aggressive driving and tailgating.

A: Ontario Transportation Ministry spokesperson Bob Nichols replies:

Where a speed reduction is required on a ramp, it is important that the posted advisory speed be both safe and realistic. If an advisory speed is too high, it will compromise safety by impacting vehicle stability, while one that is too low may also compromise safety by lowering driver compliance.

Ramp advisory speeds need to safely accommodate all types of vehicles including trucks, in all weather driving conditions (dry/wet pavement, snow cover etc.). Under optimal conditions driving certain types of cars, many motorists feel comfortable driving the ramp at speeds higher than what is posted.

Ramp advisory speeds are a function of curve radius, super-elevation rate and pavement friction factors. There are several ways to calculate the advisory speed for a ramp. The most common and practical way of determining advisory speeds on curves is referred to as the “ball bank indicator testing” and is the method used by MTO and most road authorities across North America.

Ball bank indicator readings and the resulting advisory speeds are conservative to include weather conditions and vehicle types. That is why ramps are usually posted with advisory speed signs and not regulatory speed signs.

A reminder to drivers — you could be charged with “careless driving” if you don’t adjust your speed to negotiate the ramp in safety. As most off-ramps have relatively sharp turns and a stop sign or traffic signals at the end of the ramp, it is important to observe the warning speed limit for your safety and the safety of other road users.

Eric Lai adds:

To sum up, exceeding the regulatory speed limit (white/black sign) on a highway could lead to a ticket.

Surpassing the posted “advisory” speed limit (yellow/black sign) won’t lead to a speeding ticket per se, but could result in other charges if an incident occurs.

Q: In a past article, you advised buyers to “have used cars examined by their mechanic.” How does one acquire a mechanic?

I take my 2004 Audi to the Oakville dealer for service, but I never see let alone become acquainted with a mechanic.

A: The suggestion is that you have a mechanic of your own choosing, rather than the seller’s, examine the vehicle before buying. You’re paying for it, so it’s your right to choose the service provider.

Your independent tech is more likely to tell you the whole story on vehicle condition, whereas a dealer tech or that from an affiliated shop may have a vested interest in the outcome (commission) and tailor their response accordingly.

A safety certification only means the vehicle meets certain minimum requirements and doesn’t guarantee that major repairs won’t be needed soon.

If you don’t have a regular mechanic, ask friends or family for a referral. Or, find a non-affiliated garage near the used car seller that’s willing to perform an inspection.

Post a Comment

Your email address will not be published. Required fields are marked *

*

Your Comment