By Catherine Latham, CTV News Ottawa, December 4, 2018
Four train operators were taken to hospital after a ventilation test in Ottawa's LRT tunnel went wrong.
It happened below Queen Street in Lyon Station, just after 10:00 p.m. on November 21.
“When they (train operators) arrived at Lyon station, they noticed people with gas masks on and smoke started entering the train,” says Transit Union President Clint Crabtree.
https://ottawa.ctvnews.ca/four-lrt-operators-taken-to-hospital-after-ventilation-test-goes-wrong-1.4204608