29 C.F.R. § 505.3
(a)
(1) In the absence of an alternative determination made by the Administrator under paragraph (b) of this section, and except as provided in paragraph (a)(2) of this section, the prevailing minimum compensation required to be paid under the Act to the various professional performers and related or supporting professional personnel employed on projects or productions assisted by grants from the National Endowment for the Arts and the National Endowment for the Humanities shall be the compensation (including fringe benefits) contained in collective bargaining agreements negotiated by the following national or international labor organizations or their local affiliates:
Actors' Equity Association. Screen Actors Guild, Inc. Screen Extras Guild, Inc. American Guild of Musical Artists, Inc. International Alliance of Theatrical Stage Employees and Moving Picture Machine Operators. American Federation of Musicians. National Association of Broadcast Employees and Technicians. American Federation of Television and Radio Artists. International Brotherhood of Electrical Workers. American Guild of Variety Artists. Writers Guild.
(b)