Nos. 443, 580, Dockets 89-4085, 89-4103. Argued November 29, 1989. Decided February 14, 1990. Michael T. Harren, Rochester, N.Y. (Chamberlain, D'Amanda, Oppenheimer Greenfield, Rochester, N.Y., of counsel), for Rochester Joint Bd. Gerald L. Paley, Rochester, N.Y. (Phillips, Lytle, Hitchcock, Blaine Huber, Rochester, N.Y., of counsel), for Kleen Brite Laboratories, Inc. Barbara A. Atkin, Supervising Atty., NLRB, Washington, D.C. (Joseph E. Desio, Acting Gen. Counsel, Robert E. Allen, Associate Gen