A representative from the Occupational Safety & Health Administration (OSHA) visited the Martha’s Vineyard Hospital last week following the detection of high counts of carbon monoxide in the boiler room in late March.

Oak Bluffs fire and health officials said the incident was isolated and corrected quickly.

A subcontractor working on a project in the hospital basement complained of carbon monoxide poisoning in late March and alerted the Oak Bluffs board of health. The person’s name has not released by the town due to confidentiality rules under the Health Insurance Portability and Accountability Act (HIPPA).

The Oak Bluffs fire department responded to the scene, recording an initial reading of 50 parts per million which was contaminating a small area of the boiler room.

The source of the exposure was a leak in the draft inducer blower, a part of the steam furnace, fire chief John Rose said this week. The hospital repaired the leak, and within 24 hours, the carbon monoxide reading had returned to zero, Mr. Rose said.

It was an isolated incident, he said. “Nowhere else was affected or in jeopardy,” Mr. Rose said. “The problem was rectified quickly and we have been monitoring the area,” he said.

Mr. Rose said he would continue to test the air twice a week for the remainder of April.

A report from OSHA is forthcoming.

Contacted by the Gazette on Thursday, the hospital declined to confirm the nature of the complaint.

“We are waiting to hear the results of their investigation,” said hospital spokesman Rachel Vanderhoop. “We would like to wait until we have a response and then we can speak to the claim but patients are in no danger. We don’t know that there was an exposure to anything at this moment in time.”