In the urban area, seatbelts are not mandatory in public transport buses . because other considerations than safety apply. Frequent boarding and alighting make it impractical to require passengers to wear seatbelts. Seatbelt requirements would also prohibit standing passengers and adversely affect the transport capacity of buses, trams or trains . Seatbelts are, however, required in coaches and in buses that drive ≥ 100km/h. Not much is known about the safety benefits of seatbelts in trams and buses. Mathematical models and simulation models resulted in estimates that wearing (especially three-point) seatbelts in buses may reduce injury severity in case of a roll-over crash, provided all occupants wear them properly . No account was taken of possible injuries sustained because of the seatbelts. An analysis of train crashes showed that seats with seatbelts possibly increase injury risk, compared to seats without them .