Digital Doorway Monitor
Getting Started
9
Setting Alarm-Points
The LOW ALARM and HIGH ALARM points can only be changed while the
instrument is in calibration mode. Switch the top dipswitch
CAL MODE
(behind
the calibration cover) to the right to place the instrument into calibration mode.
Changing alarm points is done by holding down the corresponding parameter key
and pressing the up or down arrow buttons. Alarm points can be set in the range
of 0.1 to 9999. When an alarm point is changed, the instrument will sound an
audible beep to confirm the saving of the parameter, and will then return to
displaying the current radiation level.
Note
Once the alarm point(s) is set, it is important to remember to switch
the
CAL MODE
switch back to the left. This action protects the
parameters from inadvertent changes.
Operational Check (Optional)
The operational check is an important assurance that the radiation detector and
electronics are working correctly.
Note
The manufacturer of this instrument suggests that an operational
check be performed on a regular basis. Local procedures may
supersede this suggestion.
For an operational check, use a radiation check source (not included, but
available). When not being used, store the check source in a secure area.
Note
Most check sources present very minimal risks and are therefore
unlicensed (Exempt Quantity Sources reference: 10 CFR 30.71
Schedule B). The radioactive element is sealed (permanently
bonded or fixed inside a capsule) so you need not wash your hands
after handling. Radiation exposure while handling this source is very
minimal with no identified long or short term risks. Although the
amount of radiation given off by exempt sources is so low that it
presents no significant hazard, they should be handled with care and
respect. Time, distance, and shielding are the best ways to control
exposure.
1. Taking the source in hand, place it so that it is located on or near the center
(same location each time) of the detector. Hold it there for approximately
5 seconds or until the reading stabilizes. Take note of the displayed level of
radiation.
2. Verify that the reading is within 20 % of the last reading obtained. Remove
the source from the detector.
3. If an alarm is activated, ensure that all visual and audible devices (if
applicable) work correctly.
4. Repeat the procedure for the other detector(s) if it was not triggered by the
first test.
