How does the National Labor Relations Act limit the board's determination of the appropriate bargaining unit?

The National Labor Relations Act (NLRA) limits the National Labor Relations Board's (NLRB) determination of the appropriate bargaining unit by requiring that such units must be based on the community of interest among employees. The NLRB must consider factors such as job duties, skills, working conditions, and interests of the employees to ensure that the unit is cohesive and representative. Additionally, the NLRA mandates that the bargaining unit must not cause undue fragmentation and that it should promote collective bargaining effectively. These criteria ensure that the chosen unit adequately reflects the employees’ interests and facilitates productive negotiations.