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| The suitable fire detectives are following: in homes: |
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| 1.Modern smoke sensors or Gadgets: |
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| These smoke sensors or gadgets may be permanently installed in buildings for the early detection of fire. |
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| The ionization-chamber type smoke detector consists of an open sensing chamber in which the air is ionized by radiation from a radioactive source. |
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| A small electrical current passes between two electrodes. Smoke entering the chamber causes a reduction in the current, which operates an electronic relay in circuit to give an alarm. |
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| 2.Optical or photocell sensors: |
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| Optical or photocell type of sensors has a beam of light scattered and absorbed by the smoke particles entering the detector. |
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| This produces a change in light intensity which may increase or decrease depending on whether scattered or transmitted light is measured. |
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| This change causes the electrical output from the light-sensitive photocell to vary and activates the alarm system. |
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| Note: Smoke detectors are efficient only if the general level of smoke or dust particles in the atmosphere is not high. Each sensor can cover a specific area. |
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