What is a key safety feature for swing doors in elevator installations?

A self-closing mechanism is a key safety feature for swing doors in elevator installations because it ensures that the doors close automatically after being opened. This is critical for maintaining an effective barrier against unauthorized access and for ensuring the safety of passengers. When doors automatically close after use, they help prevent accidents that could occur if a door remains open, such as someone accidentally walking into the elevator shaft.

In addition to enhancing safety, the self-closing mechanism also contributes to the efficiency of the elevator system by minimizing wait times and maintaining an appropriate environment within the elevator, including temperature control and air quality. This feature ultimately ensures that the elevator operates safely and effectively, safeguarding both the users and the integrity of the installation.

While other options may have their own safety benefits, the self-closing mechanism directly addresses the critical need for doors to return to a secure position, which is essential in preventing safety hazards.