Figure 1
In the Ionization detectors have an ionization chamber and the ionizing radiation. The ionizing radiation is a minute quantity of americium 241, which is a source of alpha particles. The radiation passes through the ionization chamber and the air-filled space between the two electrodes. Smoke that enters the chamber will absorb the alpha particles and will reduce the ionization and will cause the alarming. In Figure 2, the black round structure in the smoke detector is the ionization chamber. The white round structure is the piezoelectric buzzer which produces the alarm sound. Americium alpha emits particles and low energy gamma rays. It has a half life of 432 years. The long half life americium decays very slowly emitting very little radiation. Figure 2
Figure 3
There are many advantages of having a smoke detector. 13 out of 14 homes in US now have smoke detectors installed. Over sixty percent of fire deaths occur in homes without smoke detectors. First of all, smoke detector is commonly available in all shops. Secondly, whenever there is smoke enters the smoke detectors it will immediately alarm, it alerts a fire more quickly than our nose. Thirdly, smoke detectors are loud; everyone in the building can hear it when it’s alert. Then, it required in many areas, residential, commercial,
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