Calibration Certificate Results

a.temel

Starting to get Involved
#1
Our equipments are calibrated by an external lab. And in the certificate there are deviations,measurement uncertainty,repeatability standart deviation.(Caliper used to measure +-0,1mm)

1)How do we decide if the deviations of device is acceptable.Do we need to decide for what acceptance criteria should be?Is there a guideline or standart for it?(We are working for automotive)

2)I didnt quite understood the meaning of the measurement uncertainty.Is it mean the uncertainty due to environment and internal workings etc of the measurement equipment?And lets say i measured 0,55 mm and the measurement uncertainty is 0,01 mm.Does that mean my actual value might be between 0,54 and 0,56?

3)And last company i worked for used acceptance critaria below.Does that makes any sense?

(Upper Tol-Lower Tolerance)/10 <=Measurement Uncertainty+Max measured deviance

Thank in advance.
 
Elsmar Forum Sponsor

JoshuaFroud

Involved In Discussions
#2
Hi a.temel, to answer your questions;

1) I do not work in automotive, so cannot comment if there is any specific requirements there, however, for medical you need to decide for yourself if any deviation is accepteble or not. Normally there will be a defined procedure covering out of specification events and the cours eof action to follow. Normally a calibration certificate comes with tollerances which you can use as a guide.

2), Yes exactly what you said. The measurement uncerainy is the variation from the measured value. So an observed value of 1.00 with a measurement uncertainty of 0.1 could be between 0.90 and 1.10. Whereas a measured value 1.00 with a measurement uncertainy of 0.21 could be between 0.79 to 1.21.

3) I'm sorry, I have no expertise to comment on this.
 

a.temel

Starting to get Involved
#3
Hi a.temel, to answer your questions;

1) I do not work in automotive, so cannot comment if there is any specific requirements there, however, for medical you need to decide for yourself if any deviation is accepteble or not. Normally there will be a defined procedure covering out of specification events and the cours eof action to follow. Normally a calibration certificate comes with tollerances which you can use as a guide.
Thanks alot for your answer.So then i must prepare some sort of procedure that explains how to determine acceptance criteria for different equipment and what happens if calibration result are no good etc?
 

dwperron

Trusted Information Resource
#4
Our equipments are calibrated by an external lab. And in the certificate there are deviations,measurement uncertainty,repeatability standart deviation.(Caliper used to measure +-0,1mm)

1)How do we decide if the deviations of device is acceptable.Do we need to decide for what acceptance criteria should be?Is there a guideline or standart for it?(We are working for automotive)

2)I didnt quite understood the meaning of the measurement uncertainty.Is it mean the uncertainty due to environment and internal workings etc of the measurement equipment?And lets say i measured 0,55 mm and the measurement uncertainty is 0,01 mm.Does that mean my actual value might be between 0,54 and 0,56?

3)And last company i worked for used acceptance critaria below.Does that makes any sense?

(Upper Tol-Lower Tolerance)/10 <=Measurement Uncertainty+Max measured deviance

Thank in advance.

1) Your organization will need to determine what your acceptance criteria need to be. Most companies use the manufacturer's specifications of the device for this. Other companies may use guardbanding or include the calibration measurement uncertainty in their decisions. Your company needs to decide what works best in your case.

2) There are books and courses specifically for understanding measurement uncertainty. I will try to give you a very simplified explanation.
In general, the measurement uncertainty that is reported on your calibration report includes the instrument tolerance, resolution, repeatability, environmental contributors, the calibration uncertainty of the lab performing the calibration, and any other specific contributors that may be significant (such as local gravity when making force measurements). These terms are normalized and then combined by the RSS method.
You are correct in the example that you gave, the actual value has a 95% probability of being within 0.54 and 0.56.

3) The criteria formula you asked about could work, this is an example of an organization determining what is critical to them in determining acceptance on calibration results.
 
Thread starter Similar threads Forum Replies Date
F Calibration certificate content - Average Value and True Value ISO 17025 related Discussions 6
M How to read a calibration certificate for thermo hygrometer General Measurement Device and Calibration Topics 2
V Calibration certificate verification Qualification and Validation (including 21 CFR Part 11) 3
E Calibration Certificate Content Requirements General Measurement Device and Calibration Topics 3
M Accredited Calibration Sevice Provider using computerized system to issue calibration certificate Qualification and Validation (including 21 CFR Part 11) 3
M Accredited Calibration Sevice Provider using computerized system to issue calibration certificate General Measurement Device and Calibration Topics 2
G Is the calibration due date of equipment used to be on calibration certificate ISO 17025 related Discussions 38
G Calibration Certificate, fancy paper or not? General Measurement Device and Calibration Topics 9
Crusader Certificate of calibration from Manufacturer allowed? General Measurement Device and Calibration Topics 14
T Calibration Certificate Readings After Adjustment General Measurement Device and Calibration Topics 5
C Calibration Certificate "As Found" condition - TS16949 Section 7.6.2 General Measurement Device and Calibration Topics 7
M ILAC Regulations - Expression of Units on the Calibration Certificate General Measurement Device and Calibration Topics 6
A Coverage factor in calibration certificate for a multimeter General Measurement Device and Calibration Topics 4
N Client Request for Reference Equipment Calibration Certificate General Measurement Device and Calibration Topics 3
T Microsoft Access Database to create a Simple Calibration Certificate General Measurement Device and Calibration Topics 6
V How to use a Calibration Certificate in Uncertainty Calculation for a Test Measure Measurement Uncertainty (MU) 13
T Uncertainty in Hygrometer Calibration Certificate General Measurement Device and Calibration Topics 4
O How can I use reading from calibration certificate in measurement Calibration Frequency (Interval) 7
K New Gauges calibration certificate shows deviations from the measurement uncertainty IATF 16949 - Automotive Quality Systems Standard 5
Q Can we go by different Calibration Frequency vs. What's on the Certificate ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 6
R Torque Tester Calibration Traceability and Certificate question ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
S No Calibration Due Date on a Calibration Certificate unless requested by a customer? Calibration Frequency (Interval) 9
P Rounding Uncertainty to Zero on a Calibration Certificate Measurement Uncertainty (MU) 7
N Calibration Lab unable to issue Accredited Certificate when error is too high? General Measurement Device and Calibration Topics 3
S How to Evaluate a Calibration Report Certificate General Measurement Device and Calibration Topics 8
R LCP 01201P and ICPF2P Calibration Methods Stated in Calibration Certificate General Measurement Device and Calibration Topics 2
M ILAC p14:12/2010 - Accredited Calibration Certificate Uncertainty General Measurement Device and Calibration Topics 2
A Can any organization issue a Calibration Certificate? General Measurement Device and Calibration Topics 5
A No Uncertainty Listed on Calibration Certificate: Is it traceable calibration? General Measurement Device and Calibration Topics 8
M External Calibration Certificate Review ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 8
N Calibration Certificate Requirements for Pressure Gauges General Measurement Device and Calibration Topics 9
A Fluke Digital MultiMeter Calibration Traceability and Certificate General Measurement Device and Calibration Topics 11
S Reference to original Calibration Certificate - ISO 17025 Section 5.10.9 ISO 17025 related Discussions 4
howste Calibration Certificate Contents: How to report Measurement Uncertainty? Measurement Uncertainty (MU) 18
C Accredited Calibration Certificate Content - ISO 17025 Section 5.10.4.2 Question ISO 17025 related Discussions 7
D Calibration Certificate - 'test report shall not be reproduced except in full' General Measurement Device and Calibration Topics 2
howste Condition of Item Calibrated - ISO 17025 Clause 5.10.2f - Calibration Certificate ISO 17025 related Discussions 13
C Interpreting Outside Laboratory Calibration Certificate Measurement Uncertainty (MU) 3
A Calibration Certificate content for New Equipment General Measurement Device and Calibration Topics 6
R What to do after I receive a calibration certificate General Measurement Device and Calibration Topics 4
E Calibration - Manufacturer's Calibration Certificate Date ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 8
S Verification of calibration certificate Miscellaneous Environmental Standards and EMS Related Discussions 1
B ISO 17025 logo & ISO 9001 logo on calibration certificate/report ISO 17025 related Discussions 7
P Certificate of Calibration Suppliers for an ISO 9001 company ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 11
S Validity of 7 Year Old Calibration Certificate General Measurement Device and Calibration Topics 19
BradM Certificate for In-House Calibration General Measurement Device and Calibration Topics 25
Wayne Never put an Expiration (Due) Date on a Calibration Certificate Calibration Frequency (Interval) 41
J In-House Calibration Certificate wording - Confidence Level or Level of Confidence? Document Control Systems, Procedures, Forms and Templates 3
A Measurement uncertainity is not mentioned in the calibration certificate Measurement Uncertainty (MU) 4
T Class "F" Weight "Certificate of Traceability" Requirements - Calibration General Measurement Device and Calibration Topics 7

Similar threads

Top Bottom