Which safety feature provides alerts in both the FWD and AFT lavatories of the ERJ 175?

The correct answer is smoke detectors. In the ERJ 175, smoke detectors are vital safety features installed in both the forward (FWD) and aft (AFT) lavatories. They are designed to detect the presence of smoke and provide immediate alerts to the flight crew in the event of a fire or smoke-related incident, thereby enhancing the overall safety of the aircraft.

This feature is critical as lavatories can present unique fire hazards due to the presence of combustible materials, making the smoke detectors essential for early detection and response. By alerting the crew promptly, they can take necessary actions to address and manage any fire risks before they escalate.

While options such as fire alarms and emergency lighting contribute to safety, the specific function of providing alerts directly related to smoke detection is fulfilled by the smoke detectors. Oxygen masks serve a different purpose, primarily related to cabin altitude emergencies, rather than fire detection in the lavatories.