Pat Nabong/Sun-Times file Janitors who clean downtown and suburban office buildings ratified a three-year contract that provides wage increases, job recall rights and other benefit gains, their union said Monday. Service Employees International Union Local 1 said the agreement covers about 10,000 people. The negotiations involved the Buildings Owners and Managers Association of Chicago and contractors in the suburbs. Union spokesman Nick Desideri said downtown janitors secured a more than 6.3% wage hike over the life of the deal. He said that in the suburbs, janitors will see a 7.7% raise over three years plus doubled employer contributions to the 401(k) retirement plan.