The answer to 'how does smoke detector work' is that smoke detectors use sensors to detect the presence of smoke in the air, which indicates a potential fire. Most smoke detectors use one of two main technologies - ionization sensors or photoelectric sensors. Ionization smoke detectors use a small amount of radioactive material to ionize the air in the detector, creating a small electrical current. When smoke enters the detector, it disrupts this current and triggers the alarm. Photoelectric smoke detectors use a light source and a light sensor - when smoke enters the detector, it scatters the light and activates the alarm.
Smoke detectors are an important safety feature in homes, providing early warning of fires so occupants can evacuate safely. They are required by building codes in most new construction and should be installed in hallways, bedrooms, and other living areas. Properly maintaining and testing smoke detectors regularly is crucial to ensure they are working correctly and can alert you in the event of a fire.