6. TYRE SAFETY
OVERLOADING
csm51MAR2002
Prime mover overloaded on rear axle
Two tyres blew: immobilised Truck.
A following vehicle ran into rear
One Dead
Tyre overloading was a
significant contributing
factor to this fatality
7. TYRE SAFETY
OVERLOADING
csm51MAR2002
Grossly overloaded rear single axle
of Prime Mover.
Tyre blew.
Driver pulled over onto sloping hard
shoulder.
Centre of Gravity did the rest.
Tyres were overloaded- started
the sequence of events.
8. TYRE SAFETY
csm51MAR2002
Tanker was driven I Km on “Flat”
Tyre.
Tread Separated
Driver Overreacted
ROLLOVER
Running on a deflated tyre, a
significant contributory factor
in this incident
10. TYRE SAFETY
FAST and HOT = OVERHEATING
csm51MAR2002
High speed journey from
Muscat over 120kph non
stop -past Nizwa, front
tyre blew.
Rollover No seatbelts being
worn TWO DEAD
11. TYRE SAFETY
FAST and HOT
csm51MAR2002
Tread Separation. Driver lost control
ran off road.
Again, a long distance
fast trip in heat.
Tyre pressures checked??
12. Tyres are the only points of contact between your vehicle
and the road. They affect steering, braking and acceleration.
Your Safety therefore depends on a relatively small contact
patch or “tyre-footprint” area.
YOU MUST TAKE CARE OF YOUR TYRES
NEGLECTING THEM CAN COST LIVES
Most tyres nowadays are tubeless ; Constructed in a
manner that does away with an inflatable inner
tube. These tyres normally have the mark “TL” or
“Tubeless” written on their sidewalls.
TYRE SAFETY
13. TYRE SAFETY
Tubeless Tyre
Tyre and the rim of the wheel together form an
air container-the inner wall of the tyre has an
airtight lining.
Air movement during puncture of a tubeless tyre:
If a sharp object, eg. a nail, punctures the tread, air
escapes only around the nail. Generally results in
gradual deflation as long as the nail remains in the
tyre: a typical “SLOW puncture”
Tubed Tyre
Tyre is kept inflated by air in the inner tube. Air
pressure causes the tube`s valve to fit into, and
thus seal, the valve hole in the wheel rim.
Air movement during puncture of a tubed tyre:
If a sharp object goes through the tread and
puntures the tube, tube (and valve) immediately
shrink leaving the valve hole unsealed. Air
escapes QUICKLY, entire tyre collapses = flat
tyre in seconds.
14. DO NOT FIT TUBES INTO TUBELESS TYRES:
•The rubbing of the inner tube against the tyre casing
(designed to be tubeless, therefore tubeless tyres have
rougher inside linings) creates additional heat increasing the
likelihood of tyre failure.
TUBELESS TYRES HAVE BETTER
• HANDLING,
•RIDE COMFORT
•SAFETY CHARACTERISTICS
DO NOT DIMINISH THESE ADVANTAGES BY
FITTING TUBES TO TUBELESS TYRES.
TYRE SAFETY
15. DO NOT FIT TUBES INTO TUBELESS TYRES:
• By inserting a tube into a tubeless tyre it is
converted completely into a tube-type tyre and rim
combination : ie. It will deflate very quickly when
punctured, and you may lose control of the vehicle.
•The running characteristics of the tubeless tyre can
be adversely affected by inserting a tube, eg. Side
wall flexibility.
•
TYRE SAFETY
16. CHECK TYRES DAILY
•Correct tyre pressures-including spares
•Tread Depth (min1.6mm over 75% of tread width)
•No cuts, bumps or lumps
•No bulges or tears
•No mixing of different tyres on same axle (weight rating,
tread, type)
•No cord or ply showing
•Tyres suitable for vehicle use and loading
•No stones wedged between dual tyres
•Store tyres correctly-upright, in cool & dry, rotate stock
•Use a tyre cage when inflating heavy tyres
TYRE SAFETY
NEGLECTING TYRES COSTS LIVES
17. ROAD SAFETY MONITORING TEAM
csm51MAR2002
TYRE SAFETY
Partners in Road Safety
John Graham & Martin Keen
kPa bar lb/in2(psi) kPa bar lb/in2(psi)
150 1.5 22.0 200 2.0 29.0
160 1.6 23.0 210 2.1 30.5
170 1.7 24.5 220 2.2 32.0
180 1.8 26.0 230 2.3 33.5
190 1.9 27.5 240 2.4 35.0
Equivalent Pressures:
18. csm51MAR2002
THE FACTS
Partners in Road Safety
John Graham & Martin Keen
Total Vehicles Checked 2282 1186 3468
Vehicles With 1 or more Cat "A" Defects 166 294 460
Cat "A" Defects 258 427 685
Total defects (A,B,C,D) 1549 2164 3713
Tyre Defects 116 212 328
% Tyre Defects of Cat "A" Defects 45% 50% 48%
% Tyre Defects of Total Defects 7% 10% 9%
Period From 01/10/2001 To 22/03/2002
Light Vehicles Heavy Vehicles Total
ROAD SAFETY MONITORING TEAM