The incident happened Tuesday morning at a campus building on Ramapo Valley road at Ramapo College in Mahwah.
Officials say workers were on the second floor conducting a pressure test on a cooling line when it blew a gasket.
The gasket hit a construction worker who was then rushed to Hackensack University Medical Center.
The Occupational Safety and Health Administration released a statement on the incident.
"There was no explosion on site. The employees were testing an 8" chiller pipe with pressure. The employee was struck in the shoulder and head by a valve cap. The employee was transported by ambulance to Hackensack Hospital. The employee worked for Mechanical Associates of New Jersey. They had 3 employees on site. They do not have history in the past 5 years. They had an inspection on 8/11/05 incompliance, 6/16/06 issued violation for 1926.303(c)(3) grinder without guard, and 11/28/07 incompliance. OSHA is investigating the accident. They have a total of 6 months to complete it and release their findings."
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