From HFML-FELIX Wiki
ARMD
Stands for Active Radiation Monitoring Device.
There are 3 of these present at the FELIX Facility:
1: FELIX Klystron West, always turned on.
2: FEL Vault, turned off when the machine in is RUN mode,otherwise it will be on. (because the detector is sensitive and will saturate when left on).
When this detector measures high radiation values(>x uS/h) it will pulse an acoustic sounder mounted at the vault entrance door when the key is used. This is to notify the operator that precautions should be taken, or not to enter the vault.
3: FELICE Hall, always turned on
