A group of 81 San Jose, Calif. fire sprinkler testers and installers working for Cintas Fire Protection Services were awarded $1.3 million in overtime pay by the Department of Labor’s Wage and Hour Division.

The division determined that the workers were not paid for time completing reports, sending emails and submitting timesheets for the period between 2011 and 2015. Cintas refused to pay for time spent on these tasks since the work was not billable to their clients.

“Cintas shortchanged employees for some hours they worked that could not be billed to clients, despite us explaining the law to them directly in the past,” Director of the Wage and Hour Division Susana Blanco said in a statement. “Not only will dozens of workers now receive their long overdue wages, but Cintas has also agreed to a series of measures to prevent these types of violations in the future.”