International Association of Machinists and Aerospace Workers

International Brotherhood of Boilermakers, Iron Ship Builders, Blacksmiths, Forgers & Helpers, AFL-CIO

Sheet Metal Workers’ International Association

Brotherhood of Maintenance of Way Employees Division

National Conference of Firemen & Oilers

Transportation Communications International Union

International Brotherhood of Electrical Workers

Brotherhood of Railway Signalmen

Brotherhood of Locomotive Engineers and Trainmen

United Transportation Union