Canary Talk – Does your parkade CO Monitor cry like a Wolf or sing like a Canary?
Does your parkade CO Monitor cry like a Wolf or sing like a Canary?
You are probably unaware of these small boxes in your parkade that are responsible for your health or immediate safety from highly toxic exhaust gases in the air. These critical devices monitoring the air quality in your parkade behave like a cry-wolf or a singing- canary.
During the first five years of Gasonic Instruments, we were often called to deal with CO alarms and excessive fans run times. Most built-in audible alarms in CO monitors were ultimately disconnected due to many false alarms like crying wolf too often. Like in the fable, sometimes it was a real emergency that was ignored with serious consequences.
Such was the case in the early days when a dozen people were sent to hospital for CO poisoning because without an audible alarm, nobody suspected the exhaust gases from a gas-powered sweeper were making everyone sick. Carbon monoxide is odorless, tasteless and it quickly dissolves in our blood and inhibits our ability to react. It is the most dangerous gas we can encounter in our lives without being aware of its presence, thus the nickname – Silent killer.
Canadians are the most vulnerable people in the world for exposure to exhaust gases from vehicles and heating systems because of our cold climate and our love for the convenience of underground parking garages for our office and multi-residential buildings.
The canary performed very well as a hazardous gas detector for the miners in the coalmine for over a century. How could we go so wrong in commercial gas detection with advances in electronic technology? We quickly discovered that the sensor was the secret to solving this problem.
We went on a search for a better performing CO sensor. Our opportunity came in 1990 when we were contacted by a consulting engineer to provide the best performing sensor for a new City of Calgary parkade. We supplied a more costly newer sensor, but the specifications looked very promising. We were able to track the relative performance of the two different sensor technologies in two similar parkades after one year of operation. The resulting graph shown below tells an incredible story.
The sensors were exposed to 100 parts per million CO and the results were as followed:
1.Each of the orange dot on the chart to the left indicates the drift of the old sensor after one year.
- Each green dot on the right indicate the low drift of the new sensor after a year in operation.
We had found the secret to building a better performing electronic canary! However, we would face a challenge in implementing this new technology as the better sensor was ten times higher in price than the old sensor with an expected life much lower than the old sensor