ASME B89.7.3.1:2001 pdf free download CUIDELINES FOR DECISION RULES: CONSIDERING MEASUREMENT UNCERTAINTY IN DETERMINING CONFORRIIANtE TO SPECIFICATIONS
1 scoPE
These guidelines provide terminology and specifythe content that must be addressed when stating adecision rule used for deciding the acceptance or rejec-tion of a product according to specification.
2 DEFINITIONS
decision rule:a documented rule, meeting the require-ments of section 3 of these guidelines，that describeshow measurement uncertainty will be allocated withregard to accepting or rejecting a product according toits specification and the result of a measurement.binary decision rule: a decision rule with only twopossible outcomes，either acceptance or rejection.’specification zone (of an instrument or workpiece): theset of values of a characteristic between, and including,the specification limits.2.3,4
measurand:particular quantity subject to measure-ment. See VIM，2.6.5
expanded uncertainty:quantity defining an intervalabout the result of a measurement that may be expectedto encompass a large fraction of the distribution ofvalues that could reasonably be attributed to the measur-and. See GUM，2.3.5.
uncertainty interval (of a measurement):the set ofvalues of a characteristic about the result of a measure-ment that may be expected to encompass a large fractionof the distribution of values that could reasonably beattributed to the measurand,6.7
N:l decision rule: a situation where the width of thespecification zone is at least N times larger than theuncertainty interval for the measurement result.8
acceptance zone:the set of values of a characteristic,for a specified measurement process and decision rule,that results in product acceptance when a measurementresult is within this zone.9
rejection zone:the set of values of a characteristic,for a specified measurement process and decision rule,that results in product rejection when a measurementresult is within this zone.10
transition zone:the set of values of a characteristic,for a specified measurement process and decision rule,that is neither in the acceptance zone nor rejectionzone.11
stringent rejection: the situation when the rejectionzone is increased beyond the specification zone by aguard band.20
mean measurement result:results of repeated measure-ments are arithmetically averaged to yield a meanmeasurement result. The mean result is used to deter-mine acceptance or rejection.
data rejection with cause:repeated measurements mayindicate that one or more measurement results signif-cantly deviate from the rest of the results of measure-ment. If the measurement procedure has a documented
policy for addressing measurement rejection then thispolicy takes precedence.Otherwise,measurement results may only be rejected if a physical cause can beestablished. Examples of physical causes for measure-ment rejection include: improper instrument settings,loose or improperly fixtured components，known tran-sient events such as vibrations caused by doorsslamming.
3 REQUIREMENTS FOR DECISION RULES
3.1 Zone ldentification
A decision rule must have a well-documented methodof determining the location of the acceptance, rejection,and any transition zones.
3.2 Decision Outcome
Each zone of a decision rule must correspond to adocumented decision that will be implemented shouldthe result of measurement lie in that zone. While this is automatic for the acceptance and rejection zones
by definition.any transitionancenana rejection zonescorresponding decision outcome documented.
3.3 Repeated Measurements
A decision rule must state the procedure for ad-
dressing repeated measurements of the same characteris-tic on the same workpiece or instrument. See Appendix Bfor further discussion of this issue.
3.4 Data Rejection
A decision rule must state the procedure for allowingdata rejection with cause, that is,rejection of “outliers.”See Appendix C for further discussion of outliers.
ASME B89.7.3.1:2001 pdf free download
