Update 10:35am with additional details about the hazard and possible reopening time.
Technicians from General Electric are at the scene at SSM Imaging to help the Mehlville Fire Department vent helium gas from an MRI machine at the medical office.
The St. Louis Post-Dispatch says the venting should take about 15 minutes, and emergency officials hope to reopen a closed stretch of Lindbergh Blvd by noon today.
The road has been closed since last night when workers moving the MRI from the damaged medical building realized the venting system that clears helium gas was damaged during the New Year's Eve tornado. That meant it's possible the gas had built up in the building, creating the potential for an explosion.
Our earlier story:
A potential explosion hazard involving an MRI machine has forced officials to shut down Lindbergh Boulevard between East Watson and West Watson roads and the evacuation of a nearby cul-de-sac.
The St. Louis Post-Dispatch says workers at SSM Imaging, 3825 S. Lindbergh Boulevard were dismantling an MRI machine when they discovered a potential explosive situation. The machine was being moved, the paper says, because the building was severely damaged in the New Year's Eve tornado.
Sunset Hill mayor Bill Nolan told KMOV-TV (Channel 4) that workers were concerned about liquid helium in the machine turning to gas and sparking an explosion. A local fire chief says while an explosion is possible, it's not likely.
A nearby hotel offered rooms to the nine families who had to be evacuated.
In a statement to the paper, SSM Health Care-St. Louis officials say the risk of chemical or radiation exposure was minimal.
"However, since safety is our top priority, as soon as we were made aware of the issue we alerted the local public safety officials to address and secure the area," the release stated. "We are working with the manufacturer, General Electric, around the clock to determine the safest solution to resolve the danger as soon as possible."
The closure of Lindbergh was part of that emergency response plan.