TB 9-6665-285-15
b. Restrictions
(1) RADIAC instruments requiring batteries shall have a battery test mode. It is
recommended that RADIAC instruments without battery test modes be exchanged for those
with battery test mode, if available.
(2) MEDICAL instruments shall be accompanied by an appropriate dedicated
radioactive check source (built-in or owner supplied) at the time of calibration. If an
instrument is not accompanied by such a check source, it will be calibrated at ACTIVE
intervals
(3) Substitution of battery types and sizes will be permitted only when the
substitute is identified in the technical manual (TM) for the specific RADIAC instrument.
Most modern RADIAC instruments are equipped with a voltage regulating circuit and do
not require recalibration immediately after replacing batteries (calibration on or before the
calibration void date is adequate). This can be determined locally by substituting a
variable dc power supply for the RADIAC instrument batteries and by lowering the supply
voltage until the RADIAC instrument response to a check source changes. If the voltage
causing the change is below the BATTERY OK check voltage, then the RADIAC instrument
is equipped with voltage regulation. If not, return the RADIAC instrument for
recalibration when batteries fall.
(4) ACTIVE-type instruments used to measure gamma and X-rays must be
calibrated at two points on each scale with each point separated by at least 50 percent of
the maximum scale reading. Other parameter (e.g. alpha) RADIAC instruments should be
similarly calibrated when possible. This requirement specifically excludes the AN/ UDM-2
as a calibration source for ACTIVE type instruments.
(5) ACTIVE-type instruments must be kept in a separate location from TACTICAL
instruments and be readily available for use.
NOTE
Be sure all RADIAC instruments are switched to the OFF
position when not in use. Failure to do so may cause battery
failure and corroded battery compartments.
c. TB 43-180 Identifies:
(1) Calibration intervals and handling/reporting requirements for RADIAC
(2) Calibration procedures to support ACTIVE-type and TACTICAL instruments.
d. Maintenance. Calibration will be accomplished whenever repair is affected.
This is because these RADIAC instruments are usually commercial instruments with no
standardized calibration procedures or guidelines published within the Army. Additionally,
there are specific radioactive material licensing requirements and guidances associated
with ACTIVE instruments. RADIAC instruments-TACTICAL, however, are standardized
Army RADIAC instruments managed by US Army Communications and Electronics
Command (CECOM) and published Army TM's and TB's describe their maintenance and
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