Hiller Systems, Inc., was performing a safety inspection on board the M/V Cape Diamond, an ocean-going vessel, when an accident occurred involving the fire extinguishing equipment.

Two men were killed. The Occupational Safety and Health Administration (OSHA), a federal agency, attempted to investigate, but Hiller refused to permit any of its employees to speak to OSHA investigators. What could OSHA do to pursue the investigation? What limits were there on what OSHA could do?