accuracy of its calibration service. The secondary reference standards are
housed in environmentally controlled modules which must be located inside
permanent or semipermanent buildings to protect the modules from weather
conditions.
The laboratory relies on a primary standards laboratory or
other primary level activity for periodic certification of its standards and
for technical guidance.
(4) Secondary reference standards must be certified in accordance
with the intervals prescribed in TB 43-180. The primary reference facility
establishes recall schedules for the calibration of secondary reference
standards equipment.
To assure continuity of operations while secondary
reference equipment is being calibrated, duplicate items are provided in the
secondary reference standards sets.
These duplicate items are also
calibrated and certified by primary reference standards laboratories, but on
alternating and noninterfering schedules.
These duplicates are frequently
intercompared against their counterparts between calibration periods.
Intercomparison provides an indication of the reliability and operability of
both items.
(5) The secondary transfer teams use secondary transfer standards to
certify the accuracy of TMDE of supported units.
Secondary transfer
standards are calibrated at intervals prescribed in TB 43-180 and are cross-
checked during the course of the calibration loops. It should be noted here
that although, at level 1, the TASCOM calibration company is authorized
eight sets of secondary transfer standards, some of these sets may be
provided without certain items. For example, a microwave set is included in
the secondary transfer standards set, but the quantity and types of systems
provided support by the calibration company may not require use of eight
microwave sets. The determining factors are the types of systems supported,
the number of units to be provided support, and the geographical spread of
these units.
Actual requirements are determined during planning stages
before the unit is committed and its mission and assignment established.
These requirements are coordinated with the Army Metrology and Calibration
Center.
Many calibration standards are considered "limited deployment"
items.
(6) Normally, the accuracy of tactical or other using unit equipment
is certified by maintenance operational checks against certified TMDE of its
supporting maintenance unit.
When it is necessary for the calibration
company to calibrate items of using unit equipment, these items will
normally be calibrated at the site of the unit's supporting maintenance
unit.
Maintenance units are normally provided 30 days' advance notice of
scheduled visits by secondary transfer teams; using units, with at least 7
days advance notice.
When established schedules conflict with using unit
operational requirements, the using unit informs its support maintenance
unit so that calibration may be rescheduled, and so that the maintenance
unit may be able to coordinate rescheduling with the calibration company for
those items requiring secondary transfer team support. Such rescheduling,
though, must be held
37
Previous Page
