Fire and emergency services personnel provide more than just fire protection. Quite often they are called upon to extricate patients from vehicles (automobiles, trucks, buses, trains, etc.) that have been involved in accidents. Occasionally, these extrication incidents involve uncommon locations or situations where the vehicles involved may have entered the water or structures, or are hanging from overpasses or bridges. Rescue personnel may also have to extricate patients who have become entrapped in machinery or amusement park rides.