Which of the following is NOT a requirement for installing smoke detectors in a ceiling?

The requirement regarding the color of ceilings, specifically that they must be painted white, is not a standard installation criterion for smoke detectors. Smoke detectors are designed to detect smoke and heat in the environment, and their functioning is unaffected by the color of the ceiling. The main focus is on effective detection capabilities and ensuring that the detectors are placed in the best possible location for sensing smoke.

In contrast, having flat ceilings is important because irregular surfaces can impede the performance of smoke detectors. Additionally, maintaining a height of at least 8 feet ensures that the smoke detector is positioned effectively for optimum air circulation and detection. Keeping the area clear of obstructions is crucial as well, as objects can block smoke from reaching the detector, thus preventing it from functioning correctly.