Which of these measures can ensure safe operation during a fire service emergency?

Routine equipment testing and maintenance is crucial for ensuring the safe operation of elevators, especially during a fire service emergency. Regular testing and upkeep of the hoistway, along with the elevator's mechanical and electrical systems, help to identify and rectify any potential issues before they become serious. This proactive approach ensures that all safety mechanisms function correctly when needed most, particularly in emergency situations where reliable operation can be a matter of safety for passengers and responders.

While other measures, such as implementing backup power sources, training staff for manual operation, and installing automatic locks on doors, can also enhance safety and response during emergencies, they do not specifically address the operational readiness of the elevator systems like routine testing and maintenance does. It is the consistent maintenance that guarantees the systems are in optimal working condition, ultimately protecting the elevator's reliability during emergencies.