What are the PDIs on a Smoke Detector?

In the context of smoke detectors, the primary daily inspection items (PDIs) focus on ensuring that the device is properly functioning and ready for use. The correct answer encompasses two key components: the green power indicator being illuminated signifies that the smoke detector is receiving power and is operational. Additionally, ensuring that there are no obstructions is crucial, as any blockage could impede the smoke detector's ability to sense smoke effectively, potentially compromising safety.

While it's important for smoke detectors to be tested and maintained regularly, each aspect mentioned in the other choices—such as checking battery life, performing visual inspections, or replacing batteries—are typically part of regular maintenance or procedures but do not specifically represent the indicators required for a quick daily assessment. The presence of a green indicator light is a clear and simple way to ascertain that the smoke detector is functioning correctly, making it a straightforward criterion for daily inspections.