NEIEP Mechanics Practice Exam

What should be confirmed regarding the locking system when a dumbwaiter is operational?

1. The doors lock when the car is at maximum height

2. The doors lock when the car is outside the hoist way

3. The doors lock when the car reaches terminal landings

4. The doors lock at all times

The correct answer is: The doors lock when the car reaches terminal landings

The locking system of a dumbwaiter is designed to enhance safety and prevent accidents during its operation. Confirming that the doors lock when the car reaches terminal landings is crucial. This ensures that the doors only become operable when the dumbwaiter is safely positioned at the designated loading or unloading areas, effectively preventing premature access to the cab while it is in motion. By locking the doors at terminal landings, it minimizes the risk of users inadvertently opening the doors while the car is still in transit, which could lead to serious injuries or accidents. This feature is a standard safety measure incorporated into vertical transportation systems like dumbwaiters, contributing to their overall reliability and user protection. The other options imply scenarios that could compromise safety. For instance, if the doors lock only at maximum height or outside the hoist way, it could lead to situations where users are exposed to danger while the system is in operation. Therefore, focusing on the locking mechanism at terminal landings significantly enhances operational safety.