By Jim Smith

NEWTON (CBS) – A window washer at Newton-Wellesley Hospital is recovering after falling nearly 35 feet to the ground while working outside Saturday afternoon.

The accident occurred about 2 p.m. Saturday.

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The window washer fell four stories, between 30 and 40 feet, while working outside the hospital.

Emergency crews assist a window washer who fell about 35 feet to the ground at Newton-Wellesley Hospital. (WBZ-TV)

“He was on a seated platform and he was over the edge of the building, down five to 10 feet working on a window, and his harness let go and he plummeted down,” Newton Deputy Fire Chief Mike McNamara told WBZ-TV.

McNamara said the worker, a 41-year-old man, suffered severe leg injuries that were not life-threatening. He was sent to a Boston hospital.

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Fire officials say a window washer fell about 35 feet to the ground at Newton-Wellesley Hospital. (WBZ-TV)

Rescue crews couldn’t get to the worker right away because he was trapped in between two buildings.

“We couldn’t get the ambulance close enough so we had to take a scoop stretcher and carry him through a garage and then out onto the driveway, so it was difficult evacuating him,” McNamara said.

OSHA is now investigating what went wrong.

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“(It was) cold and windy and he was up quite a ways on the building,” McNamara said. “He shouldn’t have been out there this afternoon, no.”