From the “St. Louis Post-Dispatch”

Unfortunately a fourth person has died as a result of a boiler explosion at a box factory in St. Louis.

An explosion at the Loy-Lange Box Co in St. Louis sent a large boiler through the roof of the company and back down through the roof of a neighboring company, Faultless Linen Co., where it caused significant damage. The boiler weighed almost 2,000 pounds. Initially, two new employees for Faultless Linen Co. were killed and one employee from Loy-Lange was killed. Other employees were admitted to the hospital for injuries and an employee who was in the hospital from Faultless Linen Co. later died from his injuries.

The explosion affected another nearby building owned by the Pioneer Industrial Corp. but no injuries were reported there. Police had to shut down gas, electricity and water around the area.

Officials from both the United States Department of Labor’s Occupational Safety and Health Administration (OSHA) and the United States Chemical Safety Board are investigating the incident. The explosion is believed to be accidental, though investigators are looking into maintenance records and for security footage that may help them discover what happened.

The city of St. Louis does not inspect boilers but they do require businesses that use a boiler to have a licensed engineer on duty whenever they are using it. The engineers must take a course and pass a test to be licensed. One of Loy-Lange’s engineers was killed in the explosion and there are two other licensed engineers that work for the company.

Loy-Lange has violated safety standards three times since 2014. They were cited for failing to conduct annual inspections of its energy control procedure or ensure that employees were trained in proper release of stored energy to prevent injuries. They were cited for allowing a forklift to operate with no lights, damaged safety chains, missing guard rails and an improperly anchored pedestal grinder. They were cited for failing to have clean floors and aisles in disrepair in 2016. OSHA spokesperson Scott Allen said they the company addressed all of the issues and paid the fines. None of the citations were related to boiler problems.

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