No. 95-1469 Argued May 9, 1996 Decided August 20, 1996 Martin Wald argued the cause and filed the briefs for petitioner. David Habenstreit, Attorney, National Labor Relations Board, argued the cause for respondent, with whom Linda R. Sher, Associate General Counsel, Aileen A. Armstrong, Deputy Associate General Counsel, and Linda Dreeben, Supervisory Attorney, were on the brief. Stephen B. Moldof argued the cause for intervenors, with whom Judith A. Scott was on the brief. On Petition for Review