The VESDA unit

Aspirated Smoke Detection Used For Major Mittagong Project

What is an Aspirated Smoke Detector

An Aspirated Smoke Detector (ASD) uses a vacuum to actively draw air and smoke to a central detector from pipe work laid throughout a facility. This is unlike passive smoke detection systems (such as point-type smoke detectors) that have to wait until smoke reaches them to be initially detected.  Consequently, ASD’s work to detect fires early – to prevent serious damage taking place.

This makes ASD’s ideal for environments where rapid detection is required.  Environments such as clean rooms and other areas that contain goods that can be easily damaged by fire, such as factories, warehouses and areas with flammable liquids and gases. They give occupants time to extinguish a fire before the property is destroyed.

In fact, ASD’s are so effective that they can detect smoke before it is even visible to the naked eye.


It is a little-known fact that ASD’s and the original “VESDA” for Very Early Smoke Detection Apparatus, were invented and initially commercially developed in Australia.

Installing the sampling pipework.

In 1970 the CSIRO was carrying out research into bush fires and investigating fire suppression technologies that could prevent service interruptions to telephone transmission equipment during the blaze.  After selecting a sample site to carry out research, the CSIRO suggested that the “nephelometer” should be used (a scientific instrument used in labs for detecting particles in fluids and gases) to detect when the fire was approaching. The instrument was rigged with a small vacuum unit to sample the surrounding air into the nephelometer’s chamber, where it could be tested for bush fire smoke. 

At the conclusion of several weeks of testing, it was discovered that while the fire suppression equipment did not work very well, the hastily rigged-up suction and detection system showed a lot of promise for early detection of fire & smoke. 

Using this research in 1979, Xtralis Pty Ltd produced and began to sell an air/smoke sampling device they named “VESDA”.  The company redesigned the detector in 1982 to provide the reliability, features, size, and reduced cost required for export markets.

Ever since the VESDA unit has gained popularity due to its ability to sense smoke long before a catastrophic incident.   

Xtralis Pty Ltd about their current VESDA product

“VESDA” by Xtralis is a very early warning aspirating smoke detection solutions with continuous air sampling provide the earliest possible warning of an impending fire hazard. VESDA aspirating smoke detectors buy the critical time needed to investigate an alarm and initiate an appropriate response to prevent injury, property damage or business disruption. VESDA detectors have multi-level warnings and a wide range of sensitivity that does not degrade or change over time, so even minute levels of smoke can be detected before a fire has time to escalate. In addition, VESDA systems are manufactured using targeted Six Sigma techniques and ISO 9000 standards and have been certified by regulatory bodies worldwide.

Fire Safe ANZ’s Current VESDA Project

We were approached by Tyree Transformers for the specialised installation of a large VESDA system at their new substation factory.  The installation project was led by General Manager Luke Macdougall and Sean McAree our leading electrician on the South Coast and Southern Highlands. Partnering with Rob Glover from Flamestop Pty Ltd, the system was quickly re-designed to be fit for purpose and our installation team got to work.

The Vigilant MX1 Panel – the heart of the detection and warning system.

Included with the VESDA’s, the team also installed the new Vigilant MX1 Panel by Johnsons Controls to be the heart of the detection system, with conventional point-type detectors throughout the administration parts of the building. The MX1 Panel also includes the occupancy warning part of the systems that will alert the facilities workers that a fire has potentially broken out.