| necanet.org | NECA - National Electrical Contractors Association |
| afscme.org | American Federation of State, County, and Municipal Employees (AFSCME) |
| abc.org | Associated Builders and Contractors (ABC) |
| liuna.org | The Laborers' International Union of North America (LIUNA) |
| csea.com | California School Employees Association |
| ble.org | Brotherhood of Locomotive Engineers and Trainmen |
| unionlabel.org | Union Label and Service Trades Department |
| ttd.org | Ttd - Transportation Trades Department, Afl-cio |
| sbctc.org | California Building Trades Council |
| osha.gov | Occupational Safety and Health Administration (OSHA) |
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