Meteorologists expect hurricane Sandy to make landfall somewhere in New Jersey tonight. With flooding and widespread power outages predicted, imaging providers in the path of the storm will likely see their emergency preparedness plans put to the test.
In 2007, the ACR produced a report on MR safety that includes tips on emergency preparedness learned from hurricanes Katrina and Rita, which devastated large parts of the Mississippi Gulf region in 2005. They recommended:
- Cover gantries and equipment with sturdy plastic, taped in place, to keep leaking roofs or other overhead damage from dousing equipment.
- Move electronics that can be lifted as far off the ground as possible in case of flooding.
- Do not keep portable generators and other critical equipment in basement storage areas. Basements, while convenient for storage, are typically the first places to flood.
- Anticipate a power outage’s effect on MRI equipment. Without electrical power to the vacuum pump/cold head to keep the cryogen within a superconducting MRI magnet liquefied, the cryogen will begin to boil off. Depending on the design of the cryogen vent and the rate the cryogen is boiling off, the cryogenic gas discharge may freeze any accumulated water in the cryogen vent, blocking the pipe and in-creasing the odds for a cryogen vent breach in the event of a quench. If power is not restored to the vacuum pump, at some point the magnet will quench, discharging most of all its remaining cryogenic gasses and putting anyone near the MRI at that time in danger. This may happen as quickly as in a couple of days or as long as a week after power was lost.
- Only initiate a manual magnet quench with careful preparation. Naturally, you should follow the MRI manufacturer’s recommendations. In addition, the ACR report recommends “verifying the function of emergency exhaust systems, verifying or provid- ing means of pressure relief, and performing a preliminary visual inspection of the cryogen vent pipe as it leaves the MR unit to check for signs of water or ice inside the pipe (including water leaking from fittings or condensation forming on vent pipe sections).” During Katrina, one New Orleans facility that decided to quench its magnets manually reportedly experienced a failure in the quench tube and the pressure from the expanding cryogen blew out the control room radiofrequency window.
Click here to read the full 2007 ACR white paper. The emergency preparedness guidelines section is in Appendix IX.