However, the battle against an increase in sleep impaired drivers as a result of longer hours is by no means over. The trucking industry wants this increase badly, and a number of provinces continue to offer their support. According to the U.S. Department of Transportation, trucks rolling over account for about 10 per cent of all big rig crashes, and a frightening 60 per cent of big rig crashes fatal to the truck driver. The first problem contributing to rollovers is that trucks are more top heavy, and therefore are more likely to tip over. A typical tractor-trailer tips over about three times more readily than a car during a steady turn at an intersection.
Some trucks are even worse.
For example, Ontario allows single semitrailers that are even more top heavy and inclined to tip over than tractor-trailers at recommend loadings. Tanker trucks are at increased risk of rollover, because the load can shift. Tankers can also carry hazardous goods that can spill. This problem is even worse in Ontario, where certain types of tankers are allowed to be loaded more heavily. The second problem occurs at higher speeds when a double or triple trailer truck has to swerve to avoid something on the road.