DOWNERS GROVE, Ill. (CBS/WBBM) — The U.S. Occupational Safety and Health Administration is investigating what caused last Wednesday’s accident at Advocate Good Samaritan Hospital in Downers Grove.

As WBBM Newsradio 780’s Dave Marsett reports, two workers were injured this past Wednesday when two air conditioning coils fell on them and pinned them against a wall, spokeswoman Marsha Giesler said. Together, the coils weighed more than 3,000 pounds.

LISTEN: Newsradio 780’s Dave Marsett reports

The maintenance workers were in mechanical room in the hospital when the accident happened.

The worker was able to free himself enough to crawl out and called 911, Giesler said. Once summoned, emergency crews worked for about an hour and 10 minutes to free the other worker.

The Chicago Tribune says Advocate Good Samaritan said the hospital does not yet know what caused the accident.

The most severely injured of the two workers was still in fair condition at the hospital. The other worker was treated and released.

The Sun-Times Media Wire contributed to this report.

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