Marine Department inspectors will today carry out a safety audit on an Irish Ferries ship they grounded in Rosslare Harbour on Wednesday.
About 700 passengers on the MV Normandywere forced to switch to alternative services to reach their destination of Cherbourg in France.
The ship was detained after inspectors uncovered three safety deficiencies during a routine inspection.
"The deficiencies related to fire-fighting measures, safety management and crew safety training," a Marine Department spokesman said.
"It is up to the company to correct the defects and then seek a reinspection."
Irish Ferries said a technical fault was being repaired on the vessel on Wednesday evening when inspectors boarded the vessel and decided to seek a full safety audit.
Last evening a spokesman said the company was "hopeful" that the vessel would pass inspection in time for its next scheduled sailing on December 27th.
The Marine Department insisted its random inspection was one of about 1,400 carried out by its Marine Survey Office each year.
Services resumed last week on the four vessels operated by Irish Ferries after being grounded for several days over a bitter dispute between workers and management.