Dec 1 (Reuters) - Salaried workers at Monroe Energy's 185,000 barrel per day oil refinery in Trainer, Pennsylvania, started operating on a two-week rotating schedule last week to minimize the risk of COVID-19 spread, according to a source familiar with the matter.

The schedule applies to office workers, managers and supervisors but not to hourly workers, according to the source. The plant is expected to continue normal operations.

Refiners are struggling to keep essential workers at their plants safe as coronavirus cases, hospitalizations and deaths rise across the country.

Flint Hills Resources is keeping non-essential staff out at its of 375,000-barrel-per-day Pine Bend refinery in Rosemount, Minnesota, for one week after Thanksgiving to minimize risk, Reuters reported last week.

Monroe Energy did not immediately return a request for comment. (Reporting by Laura Sanicola; Editing by Leslie Adler and Cynthia Osterman)