- Deceptive Phenomena
In fire detection, deceptive phenomena is a condition or phenomena that is similar to or approximates one of the three byproducts of combustion being smoke, heat or electromagnetic radiation. Deceptive phenomena is often a cause of unwanted nuisance or false alarms.
Deceptive phenomena is not indicative of a real fire but may cause the detection system to respond as if there were one. Here are some examples of deceptive phenomena:
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Steam and Water Vapour: In areas near bathrooms, kitchens, or industrial processes involving steam, the water particles can be mistaken for smoke by some detectors.
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Dust and Particulates: In construction areas or places with heavy dust, the particles can enter the smoke detector and be misinterpreted as smoke.
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Aerosols and Sprays: Usage of aerosol sprays, such as deodorants or cleaning products, can sometimes trigger false alarms.
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Cooking Fumes: In areas near commercial kitchens, cooking fumes and even toasting bread can produce enough smoke-like particles to cause a false alarm.
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Fluctuations in Temperature and Humidity: Rapid changes in temperature or humidity, especially near HVAC systems, might cause false readings in some types of detectors.
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Insects and Small Animals: Insects or small animals getting into the detector can occasionally cause false triggers.
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Electromagnetic Interference (EMI): Interference from other electronic devices and systems might cause some detectors to react falsely.
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Cigarette Smoke: In locations where smoking is allowed or happens illegally, cigarette smoke can trigger alarms.
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Decorative Smoke Effects: In entertainment venues where theatrical smoke is used, these can set off alarms if not properly managed.
The deceptive phenomena can vary based on the specific technology used in the smoke detectors (such as ionization or photoelectric technology), and understanding these can guide appropriate placement and selection of detectors to minimize false alarms.