Most of the workers were treated and released at a camp clinic, Petroleum Development Oman said in a statement, but some required hospitalization, Gulf News reported Wednesday.
Some 62 workers were admitted and 19 were later discharged,
"All those sent to the hospitals are stable and no one is in any danger," the company said.
All of the workers were employed at oil installations in Qarn Alam in central Oman, about 250 miles from Muscat.
Petroleum Development Oman is owned by the state of Oman.
A team from the Ministry of Health has been sent to camp to investigate the incident, officials said.