Driving Risk Behaviour
SAB UCHEAGWU is a friend, a brother and a colleaguewhosecontributionshaverichlyimproved my knowledge on tyre care and the challenges it poses to road safety management in our country. Since our paths crossed some years back, he has been a mentor I will never forget in a hurry. Agood numberofthematerialsIsharewithyouarecourtesy of SAB. Today, as I look on driving risk behavior, I wish to share this rich material from him on tyre blowout hoping that travelers will get needed safety information preparatory to the December rush.
Tyre blowouts are among the major causes of fatal accidents that has claimed the lives of different categories of motorists and as we gradually await this year’s Christmas celebrations usually characterized by increased irresponsible driving, many more may still die due to tyre blowout. That is why this focus should be of serious concern for motorists planning to travel this season and even beyond this coming festive season. This piece will raiseawarenessonthemajorbutpreventablecauses of tyre blowouts and how they can be prevented.
Let us briefly look at the major causes of tyre blowouts which most people are not aware of and so are very negligent about. The major cause of tyre blowout is incorrect tyre inflation, especially under-inflation. Under-inflation causes two things that lead to tyre blowouts; It causes undue flexing of the tyes as the vehicles speeds along the undulating surface of the road. This causes a separation between the internal materials used in making the tyre and the rubber flesh that holds the materials. This separation weakens the tyre.It also causes an increase in what is known as ROLLING RESISTANCE (RR) as the vehicle moves. The increased RR generates a tremendous amount of heat. This heat, together with the separation of the internal materials of the tyre as stated above, leads to an explosion or blowout.
Incorrect tyre inflation could also cause accidents in other ways. When a tyre is incorrectly inflated (over inflation or under-inflation), it makes a partial contact with the road surface and so does not have a firm grip on the surface. With overinflation, the edges of the contact patch (the part of the tyre that should be in contact with the road surface) do not touch the ground. While with under-inflation, the crown (the middle portion of the tyre) of the contact patch does not touch the ground. So either way, you have an impartial contact of the tyre on the road surface and so less grip.
This impartial contact could cause accidents in various ways: Since the tyres don’t have a firm grip on the road surface, it prolongs the stopping distance when the brakes are applied in an emergency and this could make the vehicle crash into the object it wants to avoid. It could also lead to loss of control of the vehicle when speeding. This is more with overinflated tyres. High vehicles like trailers, tankers, etc could lose their balance when they hit a bump, pot hole, or whi;e descending a sharp bend. The situation can be likened to someone with one leg shorter than the other- over-inflation representing the longer leg while under-inflation, the shorter leg. When given a push, such a person can easily loose balance. No wonder these vehicles fall and loose brakes easily when subjected to abnormal road conditions like bumps, potholes and bends.
My friend SAB conducted a study at Orile Tanker park few years back and the study revealed some shocking results. Observations at the tanker park, Orile showed that most of these vehicles have a combination of over-inflated and under-inflated tyres. To our greatest surprise, most of those with under-inflation were deliberate. According the drivers, those tyres were weak and if properly inflated, they could burst. This is another dangerous ignorance at work. Using weak tyres is enough bad news. Under-inflating them makes matters worse. Under-inflation, as explained above, will actually accelerate their likelihood of bursting. In fact, if you trace the causes of most accidents, you may discover that incorrect tyre inflation is directly or indirectly implicated. It is important to note that a tyre that is correctly inflated will handle bad roads, speed and other road conditions far better than one that is not correctly inflated. These will result in drastic reduction in road accidents. Correct tyre pressure is such a vital issue in reduction of road accident that America, as well as some other developed countries, made it law that all vehicles manufactured from 2008 must be equipped with AUTOMATIC TYRE PRESSURE MONITORING SYSTEM (ATPMS). This device monitors tyre pressure situation every second and alerts the driver through a monitor on the dashboard about any tyre that has incorrect pressure in it so that the driver will take action before it is too late.
The second shock was the blunder prevalent among vulcanizers. An experience he had with a vulcanizer paints a grim picture of the danger all motorist could be facing on daily basis. ‘’My vehicle has ty re pressure specification of 35 psi by the manufacturer. One day, I drove into a vulcanizers shop to pump up one of my tyres. After pumping, the vulcanizer got 35psi reading on his pencil tyre gauge. I checked with my dial tyre gauge to confirm his reading and got a whooping 60 psi. I asked him to check again with his own gauge’’. Again he got 35 psi while mine still read 60 psi. Why the huge differences in reading? Who was right?
There was yet a third bl under among vulcanize rsMost vulcanize rs use the worst ty reg aug e-the pencil gauge-that malfunctions easily when subjected to heavy usage. How? These gauge has a caliberated piston that is pushed by air that comes out from the tyre when connected to the valve stem.