Stopwatch and Timer Calibrations - Aclass

FOREWORD
Foreword ◆
Stopwatch and timer calibrations are perhaps the most common calibrations
performed in the field of time and frequency metrology. Hundreds of
United States laboratories calibrate many thousands of timing devices annually
to meet legal and organizational metrology requirements. However, until
now, no definitive text has existed on the subject. This NIST Recommended
Practice Guide was created to a fill a gap in the metrology literature.
It assists the working metrologist or calibration technician by describing the
types of stopwatches and timers that require calibration, the specifications
and tolerances of these devices, the methods used to calibrate them, and
the estimated measurement uncertainties for each calibration method.
It also discusses the process of establishing measurement traceability
back to national and international standards.
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