MRI Room Alarms

Don't Panic

The Scanner Suite Environmental systems are connected to an alarm panel. Many faults in the system will trigger an alarm. Don't panic. Only the low oxygen alarm indicates possible immediate danger.

Low Oxygen
Low Oxygen Alarm Protocol
 * 1) Stop scanning and prepare to remove participant
 * 2) Open the door to the scanner suite and remove the participant. This may be a little difficult as the exhaust fan will have switched on and there will be negative pressure in the MRI room that you have to work against.  Prop the door open.  The combination of the open door and the exhaust fan should rapidly bring the O2 levels in the room back to equilibrium, and the Alarm should switch off.
 * 3) If the Alarm is still going, silence the alarm using the mute sounder button.
 * 4) If the alarm does switch off (red light on panel goes out) we now have to look for the cause of the initial O2 drop. Contact Paul Mullins and Andrew Fischer so we can have a look at the problem and ascertain if it is a Helium leak or some other environmental cause.
 * 5) If the alarm doesn't go off check the O2 numbers, and check that everyone is breathing Okay, and that no-ones lips are turning blue. This should ensure that the problem is not really related to O2 levels. If you do have difficulty breathing, or lips are turning blue, leave the scanner room if possible and close the door behind you - Get Paul or Andrew and be prepared to call security. If you can't leave the room, open the windows, call security and report the problem then call Paul Mullins or Andrew Fischer.
 * 6) If the alarm light stays on, even after checking for Helium or other gasses, it may be due to a faulty O2 sensor. The O2 sensor should last 12-18 months before needing to be replaced. If this is the case contact Paul or Andrew, who can recalibrate the sensor so it will work until a new sensor is ordered.
 * 7)    If the alarm switches off, and the room does not appear to contain a helium leak, then you can continue to scan.

Mute Sounder
Pressing the MUTE SOUNDER button will silence the alarm. It is generally a good idea to mute the sounder immediately as the audio alarm makes it hard to use the intercom.

Emergency Extract Fan Running and Ventilation Fail
Together, these two alarms indicate the emergency ventilation system is in operation. When active, a powerful fan pulls air from the magnet room. At the same time the normal MRI room AC is isolated. The emergency ventilation system is activated either by a Low Oxygen Alarm or by rotating the test switch at the bottom of the panel to the test position. If the test switch is set to normal, assume there is a low oxygen alarm even if the Low Oxygen lamp is out. The Low Oxygen lamp might be faulty. Follow the Low Oxygen protocol above. If the switch is set to test, find out why before switching the emergency system off. There may be a helium leak or other reason why the fan is running.