| These multi-purpose, wall-mounted friskers are used with the DP11 gas flow probe or our scintillation probes. Extremely easy to use, features include proven microprocessor control, a graphics display, digital setup/calibration facilities and a durable housing. Variants can be supplied: e.g. mounted on a sack truck, or with large area detectors, or with multiple detectors - details on request.
Qualities
- Peak and instantaneous readings both displayed
- Radon Recognition feature reduces nuisance alarms
- Plateau plot feature
- Gas flow probes are supplied via a pipe alongside the MHV cable, or via a quick-release valve on the body of the monitor. With the valve option, no gas connection is required during frisking
- Versatility: the dual channel CM11 operates with a large range of sensitive probes
- Ease of Use: Clear displays and annunciators, direct readout, no user controls or adjustments
- Compactness: Slim profile with suitable fixtures for mounting to a wall, a Personnel Monitor, or the bench
The CM11 is effective as an add-on device to Personnel Monitors to increase monitoring throughput rates. This contamination monitor also works well as a monitoring station during temporary work such as plant maintenance. The CM11 is ideal where space is restricted. It is easy to install and to set up, and equally easy to assign to the next application.
The CM11 is ideal as a backup boundary monitor, to confirm Personnel Monitor alarms, to pinpoint the position of contamination and amount per 100 cm2, to differentiate radon nuisance alarms from others, and for use in an emergency or when AC supplies are down. The CM11 design incorporates over 20 years of feedback from operational experience that has served to refine the specifications and add value. Better techniques are used to detect and indicate contamination. Setup has been greatly improved. Monitoring applications arise within power and fuel handling sites, also defense establishments, government laboratories, and hot labs in hospitals and industry.
Measurement
The different versions, CM11A-CM11F, carry hangers for the listed Thermo Fisher Scientific 20, 50, and 100 cm2 scintillation probes and the DP11 gas flow probe. The following types of radiation may be monitored:
- Alpha, beta, simultaneous
- Alpha plus beta
- Low energy gamma
- Simultaneous 125I and beta
Background is measured and stored until the proximity sensor is tripped or the probe lifted from the cradle, when monitoring starts. Background is then subtracted from the counts before they are displayed. A special dwell-on peak feature makes it easier to detect spots of contamination. The peak reading and the instantaneous reading are both displayed, making it easier to pinpoint the maximum reading after contamination has been detected.
Results are shown on a log scale ranging from 0.2 to 10 alarm levels, and on a digital display in units of countrate, total activity, or specific activity. The two readout channels are normally configured for alpha and beta/gamma, but can be configured to separate 125I from beta/gamma when used with the GP13 low energy gamma probe. Versions with the probe window facing out allow hands to be monitored before actually touching the probe.
Special Performance Features
- Radon recognition algorithm - eliminates nuisance alarms by distinguishing radon alarms from others
- Results displayed in count rate, total activity, or specific activity
- Peak reading, displayed during measurement, makes it easier to pinpoint the maximum activity
- Dwell on peak response assists in detecting small spots of contamination
- Gas flow and scintillation detectors both use a standard coaxial cable
- Signal processing for smoother displays of changing count rate with better detection of contamination
- Internal power source gives at least 2.5 hours operation without main power
- Graphics screen display far superior to mechanical and alphanumeric displays
- Operating point can be set by cursor from graphic display of plateau
- Built-in routines; high voltage scan, plateau plot S plus B and S2/B values for probe characterization
- Gas flow rate and pressure monitored by electronic means
- Passive infra-red proximity sensor (optional) allows hands to be monitored before touching the probe
QA Features
- A continuous self-test program prevents monitoring of invalid or fault conditions are sensed
- The probe can be tested for contamination after each measurement
- Selectable count-averaging times and confidence levels on the alarms
- Data recording possibilities, peak readings for each measurement, setup parameters, and HV scan results (using the serial port and an external printer)
Typical Applications
- Monitoring clothing in parallel with hand/foot monitors to speed up throughput
- Monitoring items next to an IPM or PCM
- Detection of radon nuisance alarms
- With a DP6 or DP11 probe, to quantify and pinpoint IPM/PCM alarms from diffuse contamination that pancake geigers cannot detect
- As a temporary monitoring station
- A workstation or exit monitor in a small zone
- As a subchangeroom monitor
- As a specialized monitor for low energy radiation
- To provide monitoring for feet, identity cards, laundry, tools, etc. in combination with special probes
Options and accessories include proximity sensor, foot switch, 1 PM mounting kit, Bench mounting kit, trolley for CM11 and gas bottle, gas bottle kit, large area check sources. Please note: Probe, cable, and accessories are ordered as separate items. For assistance in selecting the appropriate items please contact our sales staff. |