No. 86-3860. Argued January 6, 1987. Decided May 20, 1987. Kenneth A. Margolis (Dretzin Kauff, P.C., New York City, Ober, Kaler, Grimes Shriver, on brief), for respondents. Richard A. Cohen, N.L.R.B. (Rosemary M. Collyer, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Robert E. Allen, Associate Gen. Counsel, Elliott Moore, Deputy Associate Gen. Counsel, Howard E. Perlstein, Supervisory Atty., Washington, D.C., on brief), for petitioner. James M. Altman (Schulman Altman, New York City, on