Fire and microwave detectors are part of packages offered by Life Shield home security systems, but how they work and what they do varies based on the components involved.
On this page, we’ll break down how the most common ones operate and how companies integrate them into protection plans.
What are Fire and Microwave Detectors?
Fire and microwave detectors may be part of Life Shield home security systems or may work alongside the equipment you already have in place. In unmonitored setups, they may merely sound off an alarm when there are signs of a fire. With monitored setups, your alarm company will contact emergency services for help as well. If a particular system is designed to work with equipment you already have, it will likely “listen” for the siren from your existing alarm before making an emergency call. Those that work independently monitor for signs on their own.
How Do Traditional Fire Detectors Work?
Most household fire detectors don’t actually monitor for fire; they look for smoke. There are two main types which operate on similar principles.
Ionization Detectors: Ionization detectors have a chamber with a very small amount of a radioactive isotope known as Americium-241 in it. The material is safe and won’t harm your family—you’d have to open it and eat it, inhale it, or otherwise ingest it to cause a problem—but it does ionize particles (oxygen and nitrogen which are naturally in your home) that move through the chamber, meaning it removes an electron from them.
The electron has a negative charge and gets drawn to a positively-charged plate, while the positively-charged atoms get drawn to a negatively-charged plate. The plates are kept charged with a battery, so as long as it has a charge and your home has a steady supply of oxygen and nitrogen, the process continues indefinitely.
Of course, if the battery dies, the alarm will stop working, and if smoke enters the chamber, the process stops, it recognizes something is wrong and emits a sound to warn you. This type is specially-designed to catch rapid hot blazes that don’t create much smoke. However, because they’re so sensitive, they often react to any vapor, such as steam from hot showers, dust, and burnt dinners.
Photoelectric Detectors: As the name implies, photoelectric detectors use light to recognize smoke is in the air. A light-emitting diode (LED) shines inside it. When smoke comes through the chamber, it scatters the light and the light then hits a photocell, which then triggers an electrical current that sounds the alarm. This type requires a bit more smoke to scatter the light, so it works better at catching slow-burning fires that produce more smoke.
How Do Microwave Detectors Work?
When people ask about microwave detectors, they’re usually referring to microwave radiometers or MWRs. Without delving into a full science lesson, it’s a little difficult to explain the tech. However, it’s easy enough to say that microwaves are a major part of our lives, and not just for cooking food.
Microwaves are used in communication, including digital and analog transfers of voice, video, and data. Radar, such as Doppler radar which detects speed and is used in air traffic control, also relies upon microwaves. These devices measure the wavelength and frequency of microwaves as they bounce off an object, enabling the user to determine which direction the object is moving in and at what speed.
Because fires produce thermal radiation (aka heat) which creates a noticeable signal in the microwave portion of the electromagnetic spectrum, MWRs can pick up the change and therefore detect the fire. Although microwaves can’t penetrate metals, they can penetrate most other materials to varying degrees. This means that MWRs aren’t susceptible to false alerts for things like dust and steam. Researchers even believe they have a future in detecting fires through walls.
Do All Home Security Systems Include Them?
The science behind MWRs is still in it infancy, as researchers only started discussing the tech in the mid-1990s. Because of this, they’re not an option for home fire detectors as of yet, but they, as well as a whole lot of other new tech, may soon be available for homeowners.
Photoelectric and ionization detectors may be part of some home security systems, but more often than not, the systems require that you purchase and maintain your own smoke detectors. However, security system may be able to pick up on the alarm that goes off when smoke is detected and take appropriate action. Because each one operates a little differently, it’s important to get information that pertains to your particular system and components from your monitoring service or the manufacturer of the individual components.