| At least 100 feet | |
| Between 15 and 50 feet | |
| Between 15 and 50 yards | |
| At least 50 feet |
| All emergency exit doors and windows must be closed | |
| All stairways must be clear of obstacles and hazards | |
| All emergency exit handles must be functional | |
| All seats must be securely fastened to the vehicle |
| Whenever necessary | |
| When no passengers are on board | |
| At the end of a shift | |
| Only when passengers are on board |