International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers Union

International Brotherhood of Boilermakers, Iron Ship Builders, Blacksmiths, Forgers and Helpers

International Brotherhood of Electrical Workers

International Brotherhood of Teamsters

SMART Transportation Division

Transportation Communications Union/IAM

United Association of Journeymen and Apprentices of the Plumbing and Pipefitting Industry of the United States and Canada

United Mine Workers of America

Utility Workers Union of America