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The humble bird, which was employed until 1986, represents an important part of mining history
Never mind the gas—it was automation that got them in the end. Throughout much of the 20th century, chirping canaries were staples of the coal mining industry. As coal miners descended into the earth—entering a harsh environment often home to poisonous gases like carbon monoxide—they would bring the yellow birds along as safety mechanisms.
Because carbon monoxide is clear and odorless, miners needed a method for detecting a leak before it killed them. In the mine, a canary’s collapse let workers know there was poisonous gas in the air and gave them some warning time to evacuate.
But come 1981, the British government was planning the birds’ exodus, in favor of “electronic noses,” gas detectors with digital readings, as the BBC reported at the time. In December 1986, Britain officially outlawed the usage of canaries in the coal mines.
At the time, it was the latest of many changes in the British mining industry, which was a source of great strife in the country through the 1980s. In 1984 and 1985, an enormous miners’ strike halted the industry as workers rebelled against a union-busting government.
For the rest of this article: https://www.smithsonianmag.com/smart-news/what-happened-canary-coal-mine-story-how-real-life-animal-helper-became-just-metaphor-180961570/