High-risk groups
Some road users have a larger than average risk of being severely injured in a crash. Those who have no 'shell' to protect them are often refered to as 'vulnerable road users'. The most vulnerable are road users who have no vehicle and thus have no shell at all, i.e. pedestrians, and those whose vehicle does not provide an external shell around them, i.e. cyclists and light-moped riders. Moped riders and motorcyclists are only protected against head injury, at least if they wear their mandatory crash helmet.
If the unprotected body is taken as a starting point, the elderly road users are at a disadvantage because, for instance, their bones are more brittle. Their risk of a crash being fatal is higher than that of younger road users.
Road users can also be vulnerable because of their task incapability. They do not yet have much experience with their new role as road user. They have just learned to cycle, ride a moped, or drive a car. This type of vulnerability leads to a subdivision of high-risk groups by age.