What We Think We Know

Brain imageI find the interaction that I have with others on the subject of driving and traffic laws very interesting. Some people illustrate their points with incorrect information, some find that even after years of driving they don't have basic knowledge and I am always learning something new for myself. It's definitely beneficial to me and I hope that I am helping others by writing these articles. We may not be the better than average drivers that we think we are.

Discussion of the article that I wrote last week about traffic tickets not being a tax grab branched off to include the Immediate Roadside Prohibition (IRP) system in BC. I offered the opinion that any driver who received an IRP deserved it as they knew when they got behind the wheel that they should not be there. This was countered with the response that the IRP "...relies largely upon evidence provided by roadside screening devices, which are not to be confused with the far more sophisticated and accurate breathalyzer device. A breathalyzer test is admissable in a criminal trial, whereas the test of the far simpler and less accurate screening device encountered at a roadblock is not."

While I will agree that the instrument used at the detachment for breath testing is more sophisticated than the one used at the roadside, this person is mistaken as to their accuracy. When properly calibrated and utilized, both have the same accuracy of +/- 10 milligrams percent. The result of tests conducted with either instrument is also admissible in court. However, because of the way that impaired driving law in the Criminal Code is constructed, the offence of driving with a blood alcohol level of more than .08 cannot be prosecuted on the strength of the screening device reading alone.

I was also asked about a sign this week that consisted of an arrow in a red circle without a slash on a white background posted below a stop sign at the exit of a service station lot. I was confused because signs of this nature have either a green circle to show what movement is permitted or a red circle and slash to show what is forbidden. The driver went back for another look at the sign and found that it was a right arrow in a green circle. This sign requires that drivers may only exit the lot by making a right turn after stopping.

After a bit of back and forth over why this sign would be posted and how lines painted on the road here would limit some movements even without the sign I was told that much of the traffic here ignored both the signs and the lines. The drivers did what they wanted to anyway and besides, how was someone supposed to know about these obscure points in the traffic laws?

Both of these conversations illustrate that sometimes what we think we know may be in error. I suspect that the comment on the IRP stems from incomplete or poorly understood information gained from the media. Signs and lines are part of the basic knowledge required by any driver and were learned and tested with all new drivers. Unless we make an effort to reinforce what we've already learned and keep up with inevitable change, we may find ourselves without the knowledge that we need to drive properly and safely.

Some interesting input there regarding road signs.  

I was also asked about a sign this week that consisted of an arrow in a red circle without a slash on a white background posted below a stop sign at the exit of a service station lot. I was confused because signs of this nature have either a green circle to show what movement is permitted or a red circle and slash to show what is forbidden. The driver went back for another look at the sign and found that it was a right arrow in a green circle. This sign requires that drivers may only exit the lot by making a right turn after stopping.

After a bit of back and forth over why this sign would be posted and how lines painted on the road here would limit some movements even without the sign I was told that much of the traffic here ignored both the signs and the lines. The drivers did what they wanted to anyway and besides, how was someone supposed to know about these obscure points in the traffic laws?

Two things that come to mind, here.

Firstly, there has been an ongoing deliberate trend in BC (and across Canada, I think) to put signs in place that don't require words, for more universal comprehension.  With 250,000 immigrants coming to this country annually, as well as kazillions of discerning tourists, it only makes sense.  When's the last time you saw a One Way Street sign that actually said 'One Way Street' on it?  Probably twenty years ago, unless you were in another country.  Same goes for 'Yield'. Etc.  And let's face it, even if we're on federal property and a sign says 'Arret' most of us have that red octagon thing figured out anyway, yeah?

Secondly, the thinking behind those Turn Control Signs is pretty logical, really.  They're square and predominantly black and white, and therefore Rules rather than Warnings. The green circle shows a permitted action.  The red circle with a diagonal bar shows an action that is not permitted.  For the driver who is colour blind, it's the diagonal bar that indicates which message is being given.  At a T-junction where a driver isn't allowed to turn left, they could put up a sign with arrows pointing left and also sraight, using a red circle and bar; but why bother making it that complicated?  So the traffic engineer simply erects a sign with an arrow bending right with a green circle around it to say the same thing.

Sometimes, even Traffic Engineers make mistakes in usage; a relatively common one is where they use a Lane Use Sign - that's a square black sign with some kind of white arrow(s) on it at an intersection - but these are actually only supposed to be placed prior to the situation, so that drivers have the opportunity to change lanes if necessary in order to continue where they want to go.  Typically, their message will be reinforced by white arrows on the black roadway lanes. And the dashed white lines between the lanes will be painted solid white from the point where lane changes are no longer permitted.

As Drive Smart BC points out, this stuff is far from obscure; it's fundamental.  I could show you BC Driving Guides from the 1970's that have this information in them.