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3.0
CALIBRATION AND RECERTIFICATION
The accuracy of measurements can only be ensured through calibration against reference
standards of a known and well characterized measurement uncertainty; reference stan-
dards that are ultimately traceable through a national standards laboratory to the Interna-
tional Bureau of Weights and Measures (BIPM), to a natural physical constant, or to consen-
sus standards.
All AMETEK pressure calibrations are traceable in the United States of America to reference
masters calibrated by the National Institute of Standards and Technology (NIST).
Measurement performance is affected by the frequency and severity of use, the environ-
ment, test conditions, and by other factors. AMETEK recommends calibration on a pre-
scr bed interval/frequency in order to ensure optimal measurement performance and reli-
ability.
Two types of calibration services are offered:
G
Calibration with a Certificate of Conformance/Certificate of Compliance
A statement of conformity which documents that the listed device(s) conforms to pub-
lished specifications, or the terms of the order/contract. It can provide, in addition, a
statement of traceability to NIST.
G
Calibration with a Cal bration Report/Certificate
A report that outlines detailed information about the calibration process. This includes
actual calibration data, traceability information, test conditions, and other factors as may
be applicable to the type of device being calibrated.
3.1
RECOMMENDED CALIBRATION FREQUENCY
As a general rule, AMETEK
pneumatic testers should be tested and recertified every 12
months.
Testers used on a more frequent basis should be tested more frequently.
3.2
MATERIALS NECESSARY FOR RECERTIFICATION
Both the tester assembly and weight set should be returned to AMETEK in order to allow for
calibration of the tester as a
“
system
”
. Pressure is a derived parameter requiring determina-
tions of both effective area and force (weight-mass). Instruments not sent to AMETEK as
a
“
system
”
can only be provided with certifications on the parameter calibrated, e.g. effec-
tive area or mass.
All materials should be securely packaged to prevent damage during transportation and
handling. Testers should be returned in their case. The ball/nozzle assembly should be
wrapped with adequate padding material and well secured to avoid shifting, movement and
to protect them from shock during transportation.
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
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