As of April 30, 2012, most private sector employers will be required to post a notice advising employees of their rights under the National Labor Relations Act. This requirement applies to a variety of entities with a gross annual volume of at least $250,000.00. The poster is available for free at https://www.nlrb.gov/poster or by calling (202) 273-0064.
In addition to the NLRA poster, the U.S. government requires the posting of these workplace posters: 1) Employee Polygraph Protection, 2) Equal Employment Opportunity, 3) Fair Labor Standards Act, 4) Job Safety and Health Protection, 5) Rights Under the Family and Medical Leave Act (for employers of 50 or more individuals), and 6) Uniformed Services Employment and Reemployment Rights Act. You can obtain them for free from the U.S. Department of Labor Web site www.dol.gov/compliance/topics/oster.htm.