How it Works – Cloud Chamber Detection

The cloud chamber is a fire detection method that dates back many decades. Protec has been manufacturing cloud chamber technology aspirating detectors for over twenty years. The unique technology has proved to be one of the most accurate types of detection in the fire detection industry. The very early warning capabilities prove to be a formidable weapon in the fight against fires at the earliest possible stage. The science behind cloud chamber detection should not be underestimated, and this article will try to remove all the smoke and mirrors from the cloud chamber to explain how it works.

Cloud Chamber Technology

Aspirating Detectors the Basics

Let’s start with the basics of an aspirating detector. In simple terms, an aspirating detector is a unit that sucks air in and looks for combustion particles (fire or smoke) in the air sample. It inhales air into the detector every few seconds through a series of perforated pipes. It then looks at this air sample to see if fire/smoke particles are present. The detector inspects the air using either a Cloud Chamber Detector (CCD) or a Scatter Chamber Detector (SCD) The most advanced aspirating detectors use a combination of both technologies to offer superior detection (like our Cirrus HYBRID, but that’s for another article in the future). Should the aspirating detector find any traces of fire/smoke particles in the air, it will then activate a local alarm on the detector and notify the main fire alarm panel to trigger the required response.


Protec Cirrus CCD Detector


What’s Inside a Cloud Chamber Aspirating Detector?

To understand how a cloud chamber detector works, we must look at what components make up a cloud chamber type aspirating detector; these include:

  • Aspirating pipework
  • Inlet ports
  • Aspirating fan
  • Vacuum pump
  • Humidifier chamber
  • Cloud Chamber
  • Cloud forming fluid

It starts in the field where the aspirating pipework protects the selected area/room. The pipes are installed in the different areas/rooms in line with current relevant design standards for the application.; These pipes have a set number of holes along the protected area where the air is drawn into the detector via the inlet ports using an aspirating fan.


The Cloud Chamber – Where the Magic Happens

Once the air sample is pulled into the cloud chamber, a tiny amount of cloud-forming fluid (a bit like water) is added to the chamber. The vacuum pump then sucks the air out of the chamber, dropping the pressure, which lowers the temperature, causing small clouds to form ON ALL Fire Particles. These clouds are then analysed using an optical sensor. The cloud chamber then releases the pressure, the clouds dissipate, and then the air is pushed out through the exhaust port, and the air sampling cycle starts again.



When air is sampled, the more fire particles that are present then, the denser the cloud will be. The optical sensor analyses this air sample containing the fire particles; the detector sees the increase in cloud thickness and provides a signal to the main fire alarm system.


Final Words

So there you have it—a brief outline of how our cloud system technology works. A simple method which proves great in detecting fires at a very early stage; after all, the sooner you can detect a fire, the sooner you can tackle a fire. Contact our sales team today if you want to know more about our aspirating systems or any other fire detection technologies or products.