TB 9-4931-537-24
GENERAL
1. Purpose. This bulletin provides guidance and procedures applicable to the cross-
checks, intercomparisons, and visual inspections of measurement standards.
2. Applicability. This bulletin is applicable to all TMDE support activities (TSA), Army
National Guard (ARNG), and Government owned contractor operated facilities (GOCO),
except the U.S. Army Primary Standards Laboratory (APSL).
3. Definitions
a. Cross-check. A secondary transfer level functional comparison between selected
measurement standards to verify that no significant departure from assigned tolerances
has occurred.
b. Intercomparison.
A secondary reference level functional comparison, or
operational check, between measurement standards to verify that no significant departure
from assigned tolerances has occurred.
c. Visual Inspection.
The physical inspection of a measurement standard for
apparent damage.
4. Policy
a. Cross-checks will be performed on designated transfer level measurement
standards, or equivalents, to verify the standards have not been damaged or accuracy
degraded during shipment and/or to prevent out-of-tolerance standards from being used to
perform calibrations.
b. Intercomparison checks will be performed by all reference level activities and
activities with reference level or higher capabilities. The intercomparison check is required
on reference level measurement standards being calibrated by the equipment manufacturer
or higher calibration activity. This intercomparison will encompass enough cardinal points
to convince the person performing the intercomparison that the item meets all required
specifications.
c. A visual inspection will be performed on measurement standards that are received
from another calibration activity not located in the same building. These inspections are
performed to assure that standards have not been damaged or degraded during
transportation.
