Avoiding Injury if You Do Rollover
The only good protection against rollover injuries is roof strength. Most domestic and Asian vehicle makers do not provide adequate roof strength in their vehicles because the governing Federal law (FMVSS 571.216) is inadequate. Many European manufacturers do. Volvo, Mercedes Benz and BMW make the best vehicles in terms of rollover protection. The situation with the other European makes is not clear. Seatbelts usually prevent ejection, and ejection can lead to serious injuries (see below), but seat belts generally do not prevent roof contact in rollovers, especially if the roof collapses. Inflatable devices designed for rollover protection (not frontal air bags) may offer some protection, but the proof is not yet available. They should almost certainly be purchased with a new SUV if available however.
The cause of serious injury for non-ejected occupants in rollovers is roof crush. (See: "Causes.pdf") Head and neck injuries are the most common types of serious rollover injuries. If the vehicle is going over, the best thing to do is to get your head out of the way if you can do it before ground contact, but this may be difficult if not impossible. It will also be difficult, if not impossible to brace yourself with your hand against the roof. Even if you can do it in time, you will be thrown around too much as the vehicle rolls and strikes the ground for this to be an effective technique. (Even if belted, the upper body will move around a lot.). Probably the only thing that might prove beneficial is to put your arm over your head and grab the opposite ear and try to hold on to it. Better to loose your arm or your ear than your head or neck.
Ejection correlates highly with injuries in rollover accidents. Most ejections are through window glass that is broken during the rollover. But some are probably through windows that were open before the rollover rather than broken during the rollover. So keep the windows up and moonroofs closed as much as possible. If your vehicle does not have automatic door locks, make sure the doors are locked before you move. Never run with an open tailgate. Doors and tailgates are also ejection portals.
Additional Safety Tips
SUV's and 4 X 4s rollover easily because they are high and narrow. Get the lowest -shortest - tire and wheel combination that will support the fully loaded weight of the vehicle. Keep the weight- payload -low in the vehicle. People are the worst thing to put in an SUV because they tend to raise the c.g. and make it more likely to rollover. Older vehicles with degraded suspensions, e.g., worn shocks, may be easier to roll than vehicles with good suspensions. Tire pressure is also important in complicated ways. Underinflated tires are dangerous because they are more likely to experience heat related catastrophic failures. Check tire pressure regularly, at least weekly. The tire manufacturer's maximum recommended pressure is probably best for most vehicles, The vehicle manufacturer's recommended pressure may be on the low side to produce a softer ride. Now, pressures on the high side - less than maximum but over the minimum- may also increase cornering traction and thus and increase the chance of a rollover. But tires which are operated at the maximum pressure tend to have reduced contact area and thus produce less cornering force which is good for SUV's and 4 x 4s. They are also suppose to be more vulnerable to punctures, so check air pressure frequently. Hard tires have improved cornering stiffness (very roughly -how quickly and how well they respond to steering inputs) which is probably good for competent drivers. Better steering tires may reduce the chances of "oversteering" since you get more response earlier and are less likely to try to compensate for the lag.
NEVER put oversized tires on an SUV or 4 x 4 even if they are not higher. Any increase in cornering traction is dangerous in these vehicles. The improvements in straight line performance can never be worth it.
High passenger vehicles are extremely vulnerable at intersections because they can be jacked over when hit in the side by lower vehicles. (See Tempo)
NEVER take the kids to school in an SUV if they can ride in a school bus. School busses (the big ones, not converted vans) are at least 100 times safer than SUV's.