Employer's Safety Concerns Were Not Sufficient To Avoid Its Obligations Under Its Collective Agreement

An Employer was required to revert to a previous shift schedule in accordance with its obligations under the collective agreement, notwithstanding its claim that the previous shift schedule was less safe.

Initially, the majority of the employees at the Employer's mine worked a rotating 2X2 shift schedule whereby employees each worked 12 hour shifts. They worked 2 day shifts, had a 24 hour break, followed by 2 night shifts and then 4 days off.

In 2014, after more than a year of negotiations, the Employer and the Union entered into a Memorandum of Agreement which included 2 Letters of Understanding setting out a new shift schedule. The new shift schedule was a 4X4 rotating shift. Employees would continue working 12 hour shifts but would do so in 4 day shifts, followed by 4 days off, then work 4 night shifts, followed by 4 days off.  The agreement was for a 9 month trial period after which employees would vote on whether they wanted to continue permanently with the