No. 87-1756. Heard March 8, 1988. Decided August 3, 1988. Carlos Bobonis Gonzalez with whom Bobonis, Bobonis Rodriguez Poventud, Santurce, P.R., was on brief for petitioner. Howard E. Perlstein, Supervisory Atty., with whom Rosemary M. Collyer, Gen. Counsel, John E. Higgins, Jr., Deputy Gen. Counsel, Robert E. Allen, Associate Gen. Counsel, and Aileen A. Armstrong, Deputy Associate Gen. Counsel, Washington, D.C., were on brief for respondent. Petition from the National Labor Relations Board. Before