TOO MUCH HEAT CAN CAUSE A TIRE TO HAVE AN
EXPLOSION (SUDDEN BREAK)
Explosions of pneumatic tires have resulted from
heat-causing gas combustion inside the tires. The
components, fire, or too much use of brakes, can
cause gas combustion.
A tire explosion is much more violent than a
blowout. The explosion can throw the tire, rim
and final drive components as far as 460 m (1500
ft.) or more from the machine. Both the force of
the explosion and the debris can cause personal
injury or death, and property damage.
Although an explosion is not probable, the hazard
(danger) is very great, especially with large tires
used on wheel tractor-scrapers.
All personnel must know of this danger and the
actions to take to keep the risk at a minimum.
Heat from any source can be sent to the tire. This
causes deterioration (decrease in quality) of the bead.
Normally, the burned bead causes loss of air, and the
tire goes flat without danger to anyone in the area.
A bead that is burnt can result in the release of an
explosive mixture of gas inside the tire. It is possible for
the mixture of gas inside the tire to burn. The fire inside
the tire causes a rapid increase in pressure. The result
is a violent tire explosion. The explosion causes a
blowout at the tire bead which throws the tire, rim
assembly and final drive components far away from the
When a wheel is in rotation, the movement of air
around the tire helps in cooling the tire. There is more
danger of a tire explosion after the machine stops,
because of the loss of this cooling effect.
If smoke, too much heat, the smell of burning rubber
or hot brakes, or other indications of bead burning are
noticed, take action to prevent personal injury.
Move the machine to a remote area, but only if it can
be done without danger to the operator or other
personnel in the area.
Remove all personnel in the area of the machine.
APPROACH AREAS. Do not get within 460 m
(1500 ft.) from the side or within 15 m (50 ft.) from
the front, rear or above a tire.
Do not go near any tire on the machine if there is a
brake fire, burning rubber or other indications that the
brakes have caused too much heat. This heat can have
an effect on all other tires on the machine, even though
the visual indication is only at one tire.
If there is an indication of a brake fire or the smell of
burning rubber, do not go near the machine. FIGHT (put
out) THESE FIRES FROM A REMOTE LOCATION.
(Many times, the immediate action to a fire caused by
tires or brakes, is for people to use a hand fire
extinguisher and run up close to the machine to help put
out the fire.) Keep away from the machine until the tires
cool (temperature decreases). Permit at least eight
hours for the tires to cool before a person goes near the
Keep personnel out of the area, and at least 460 m
(1500 ft.) away from the side of the tire and 15 m (50 ft.)
away from the front or rear of the machine.
A small fire caused by debris on the machine is not a
hazard. This type of fire can be put out with a hand fire
extinguisher. A burning (smoking) tire or fire in the brake
area is hazardous. These are sure indications of a hot
tire. There is no completely safe way to get near a
machine to put out this type of hazardous fire. Go near
only at the front or rear of a machine and use a large
bulldozer as a shield.