Many amazing devices have emerged that have helped save the lives of thousands of people. One such device is the smoke detector, which is recommended for every home, shop, business, and other place.
However, the question of how a smoke detector works may preoccupy many people considering purchasing this device, which is why we have addressed this topic and explained it in the following lines.
How does a smoke detector work?
You should first know that all smoke detectors consist of two basic parts: a sensor that detects smoke, and an electronic smoke horn that produces a loud alarm sound. In the following lines, we will explain how the two most commonly used and popular types of smoke detectors work.
1. Photoelectric smoke detector
This type of smoke detector operates using light beams. It consists of two parts: the first is a white lamp and a low-power lens or laser, and the second is a detector to detect the light. These are mounted on opposite sides at a 90-degree angle. When anything prevents this light beam from reaching the detector, it immediately reports the absence of light and emits a loud, audible bell sound.
When smoke spreads in an area where a photoelectric smoke detector is located, the light reaching the device is blocked, thus triggering a fire alarm and prompting everyone to leave the area immediately.
But this device has two drawbacks:
- This device is large in size, so it may not fit in tight spaces.
- He has a weak ability to sense smoke, so he warns of a fire after the place is filled with smoke, which may lead to the problem getting worse and not being aware of it from the beginning.
2. Ionic smoke detector
It is the most common and widely used type of smoke detector, due to its excellent ability to detect smoke, especially in small quantities. The device operates using a small amount of americium-241, a radioactive element that emits radiation for up to 432 years, making it a good source of alpha particles.
Inside this device is an ionizing chamber made up of two opposite plates between which an electric current passes. It also contains a radioactive source for ionizing radiation. From this chamber, the process begins, and the following occurs:
- Alpha particles begin to emerge from the opening in the lower plate, as the ionization of air molecules between the two plates causes an electric current to pass between them. This is due to the ability of the alpha particles generated by the americium to ionize both oxygen and nitrogen atoms in the air.
- Inside the chamber, electrons are released, some becoming positive ions and heading towards the plate connected to the negative electrode, and others becoming negative ions and heading towards the plate connected to the positive electrode. Thus, an electric current flows continuously within the electrical circuit as a result of the radioactive element ionizing the air atoms.
- If smoke spreads in the area where the smoke detector is located, it will seep into the ionization chamber and cause disturbance in the current. The device will sense that the current has decreased and trigger the fire alarm.
What element is used in some smoke detectors?
Americium-241 is a very small element that undergoes a transformation by releasing both energy and alpha particles that have a very high speed to travel through air, thus conducting an electric current. Once the smoke penetrates this electric current, the device begins to sound the alarm.
What is the best place to put a smoke detector?
A smoke detector can be placed anywhere in your home, for example:
- The kitchen: The most suitable place to place a smoke detector is in this area, as fires start there. It is recommended that it be placed approximately 10 feet away from the stove or oven. If the kitchen is small, it can be placed directly outside it, 10 feet away.
- Bedroom: The smoke detector can be placed inside or just outside the bedroom.
How do smoke detectors and heat detectors work?
Smoke detector: Sounds an alarm when smoke is detected in the air.
Heat Detector: Sounds the fire alarm once the temperature around it reaches a certain level.
Is the smoke detector radioactive?
There is a type of smoke detector that works with a radioactive element such as americium-241, which can remain radioactive for 432 years. This radioactive element is the primary factor in detecting smoke, and the device cannot function without it.
Types of smoke detectors
There are several types of smoke detectors, each of which operates with different components and its own unique method. Each of them has its own advantages over the other. These types are:
- ionization smoke detector
- Optical smoke detector
- Light-emitting dimming smoke detector
Best Smoke Detector
No device is better than another, but each has its own advantages and features that make it more suitable for a person and a place than another. However, it can be said that the smart smoke detectors that have been released and widely used recently have unique features and very good sensitivity to smoke.
How to disable a smoke detector
Many of these smoke detectors come with a button on the front that when pressed for a few seconds will turn off the alarm.
If your smoke detector doesn't have an alarm shutdown button, you should clear the smoke that triggered the detector, then turn on the fans and open the windows to circulate the air and push it out of the area where the detector is located.
Smoke detector in hotels
Hotels have a large number of rooms, and therefore a large number of guests of various nationalities. Therefore, all hotels have more than one smoke detector to detect any fire in its early stages, thus helping to protect the lives of all guests.
Optical smoke detector
A type of smoke detector that operates using LED indicators, thus transmitting a signal to the control panel indicating the presence of smoke in the area. This type is often used extensively in various commercial establishments.
Smoke detector installation
- Smoke detectors are often installed in ceilings and should be located in the center of the ceiling and 30 cm away from the walls.
- The device comes with a mounting base, which must first be placed on the ceiling and then the device must be mounted on it.
- The base has two holes into which screws are placed for installation.
- Installing the device is simple by placing it on the base and turning it clockwise.
- It can be tested by pressing the test button to test it.
Does a smoke detector detect cigarettes?
Yes, smoke detectors are often sensitive to cigarette smoke.
smart smoke detector
The smart smoke detector comes with different features than other devices, which are as follows:
- Connects to your mobile via Wi-Fi
- Sends an instant notification to your mobile phone in case of heavy smoke
How does a gas detector work?
The outer shell of the gas detector has multiple openings in different directions. The sensors detect the presence of high gas concentrations in the air and thus activate the alarm.
Smoke detector coverage area
The smoke detector covers an area of 60 square meters and is recommended for placement in areas prone to fire.
Best Smoke Detector
- a Reflex 5TC1292
- Nest Protect Smoke and CO Alarm (2nd Gen) Smart Smoke Detector
- First Alert Smoke Detector Photoelectric and Ionized Alarm
- Best Budget Smoke Detector: Kidde i12040 120V AC Wire-In Smoke Alarm
- Best Fire Smoke Detector “OneLink Safe & Sound by First Alert”
- Best Wireless Smoke Detector “Ardwolf Photoelectric Smoke and Fire Alarm”
- Best Battery Smoke Detector “ADT Smoke Detector”
- The best environmentally friendly smoke detector “Alert Pro 10 Year Battery Smoke Detector Fire Alarm”
We have thus explained to all inquirers how a smoke detector works, in addition to providing other valuable information about this type of device that you will greatly benefit from reading.
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