EVALUATION EXAMS 2026 FULL SOLUTION
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◉ smoke detectors
Answer: detects visible or invisible particles of
combustion
◉ smoke detectors or heat detectors are faster?
Answer: smoke detectors
◉ smoke detectors are helpful because ... (2)
Answer: 1. early warning of a fire
2. occupants can evacuate immediately after warning
◉ Ionization detectors
Answer: use an ionization chamber and a source of ionizing
radiation to detect smoke.
better at detecting the smaller amounts of particles of combustion.
, Monitor 'ions,' or electrically charged particles in the air. Smoke
particles
entering the sensing chamber change the electrical balance of the
air. The greater
the amount of smoke, the higher the electrical imbalance.
When combustion
particles enter the smoke detector, they obstruct the flow of the
current. When
the current gets too low, the system actives the alarm.
◉ photoelectric detectors
Answer: better at sensing smoky fires, such as those
caused by a smoldering mattress.
Light from the light source in a photoelectric
detector may be reflected off the walls of the sensing chamber, and
be seen by the
photosensitive device when no smoke is present. Insects, dirt,
drywall dust, and
other forms of contamination can accumulate in the sensing
chamber and reflect
light from the light source onto the photosensitive device; as a result
detectors