When the existing Irvington Tunnel was constructed miners might have used canaries to warn them of dangerous gases.
Meet the modern day canary. Like its feathered forbearer it alerts miners to presence of dangerous gasses underground. However, instead of wings and a beak, today’s canary- a handheld gas detector is encased in rugged rubberized armor and has ultra-bright LED alarms.
Handheld gas detectors are operated by a certified gas tester that accompanies each tunnel crew underground. The modern canary tests for oxygen content, hydrogen sulfide, carbon monoxide, carbon dioxide, nitrogen dioxide and explosive gases like methane. If certain levels explosive or hazardous gases are detected then LED lights flash and an audible alarm is sounded.
Gas levels dictate the strict safety procedures the crews follow. If gas levels are detected at 10% LEL or Lower Explosive Limit, then steps are taken to increase ventilation in the tunnel. Work can continue but must be performed with extra care. If gas levels reach 20% LEL then electric power is shutdown and miners must evacuate the tunnel.
Safety comes first inside of the New Irvington Tunnel. Miners take great care to check their surroundings when operating hundreds of feet below ground. For the risks they can’t see with the naked eye, the modern canary- a handheld gas detector has their back.