UPDATE 1-Murphy Oil to shut Meraux, La. refinery for work

(Adds OSHA citation, quote)

HOUSTON, Dec. 31 (Reuters) - Murphy Oil (MUR.N) on Monday will begin shutting down its 125,000 barrel-per-day refinery in Meraux, Louisiana, for a planned 30-day full turnaround, a spokesman said.

The turnaround will involve work on several key units, including the crude distillation unit, platformer and the middle distillate hydrotreater.

Separately, Murphy was cited this week by regulators for 18 "alleged serious violations" of health and safety standards at the Meraux plant.

Spokesman Craig Bonsall declined comment on the U.S. Occupational Safety and Health Administration's citation or proposed $85,000 fine.

He would not say whether Murphy would contest the citation and fine, comply or seek a conference with OSHA's area director in Baton Rouge, Louisiana.

"I have no response," Bonsall said.

OSHA said in a statement that the agency began investigating the plant on July 7.

Alleged violations include failure to provide a design for relief systems to prevent fires or explosions in the hydrocracker unit; lack of a sufficient written mechanical integrity program; failure to regularly inspect pipes; and failure to report findings and recommendations from incident investigations.

The Meraux refinery employs about 315 workers. (Reporting by Kristen Hays; Editing by David Gregorio)