The gate switch must not close until the door is within how many inches from the close jamb?

The correct answer indicates that the gate switch must not close until the door is within 2 inches of the close jamb. This requirement ensures proper functionality and safety within the hoistway system. Keeping a 2-inch threshold is crucial for preventing the door from closing too early, which could lead to potential safety hazards for passengers and maintenance workers. If the door were to close prematurely, it might not engage securely with the jamb, creating risks of entrapment, misalignment, or failures in the door mechanism.

This specific distance ensures that the gate switch accurately detects the position of the door and allows for safe operation. This standard is likely based on both functional requirements and safety regulations that govern elevator and hoistway maintenance practices. Adhering to these specifications helps ensure that the elevator doors function safely and reduce the risk of accidents.