CALIBRATION TRAINING

1. HELLO!
Iam YK Tang
| HRDC Trainer | Quality & Process Improvement
Specialist | Supply Chain Black Belt | Pro
Photographer | Coffee addict | Car enthusiast 1

2. Measurement
• Our daily life is based on measurement
• Measurement is the first step that leads to control and
eventually to improvement - if you cant measure
something, you cant understand it.
• If you cant understand it, you cant control it, and if you cant
control it, you cant improve it.

3. • Measurements are made to support decisions or establish
facts. If measurement data are not used in a decision, the
measurement is unnecessary
• So, how much can we trust our data / measurement?

4. Think
• What if pasar malam hawker’s scales not accurate?
• What if police speed trap radar gun is not accurate?

5. Measurement error – what can lead to ?
• Measurement error is considered to be the
difference between a value measured and the
true value.
• Error in Measurement will results in alpha and
beta risks for both the producing organization
and its customers
• Type 1 error = producer risk = false alarm
• Type 2 error = consumer’s risk = miss rate
• False alarm rate + miss rate = Error rate
Good NG
Reject
Accept
OK
OK

6. What is Calibration? definition
• Process of comparing of a measuring equipment with a
reference standard to detect and quantify measurement
errors and to report or eliminate these errors
• Measurement of Accuracy
· Establishment the relation of an instrument’s accuracy to
the international standard

7. Calibration Traceability

8. CALIBRATION VS VERIFICATION

9. Calibration needs in ISO9001:2015
• Element XXX ?? refers to monitoring and measuring
resources
• What are monitoring and measuring resources?

10. ISO9001:2015
• The organization shall determine and provide the resources needed to ensure valid and
reliable results when monitoring or measuring is used to verify the conformity of
products and services to requirements
• The organization shall ensure that the resources provided:
– A) are suitable for the specific type of monitoring and measurement activities being
undertaken;
– B) are maintained to ensure their continuing fitness for their purpose
• The organization shall retain appropriate documented info as evidence of fitness for
purpose of the monitoring and measurement process

11. ISO9001:2015: Measurement Traceability
• When measurement traceability is a requirement, or is considered by the organization to be
an essential part of providing confidence in the validity of measurement results, measuring
equipment shall be:
– A) calibrated or verified, or both, at specified intervals, or prior to use, against
measurement standards traceable to international or national measurement standards;
when no such standards exist, the basis used for calibration or verification shall be
retained as documented information
– B) Identified in order to determine their status
– C) safeguarded from adjustments, damage, or deterioration that would invalidate the
calibration status and subsequent measurement results
• The organization shall determine if the validity of previous measurement
results has been adversely affected when measuring equipment is found to be
unfit for its intended purpose, and shall take appropriate action as necessary

12. UNDERSTAND SOME CALIBRATION
TERMINOLOGY

13. • There is no such thing as perfect measurement
• All measurements have errors and uncertainties, no matter
how hard we might try to minimize them

14. What is an error?
• Measured Value – True Value
• Example, assume a stick rod of true value
of 25mm, and a measured value of
24mm, therefore the error is 1mm
Reference Value
Accuracy
(Bias/error)
Distribution of repeated
measures on a single
specimen or part
Precision
- Repeatability
- Reproducibility

15. Example calculation
• Actual value, true value = 0.20
0.21 0.25 0.23
0.22 0.21 0.20
0.20 0.20 0.21
0.23 0.19 0.24
0.20 0.18 0.23
0.21 0.20 0.22
What is the measurement error?
Average = 0.213
Measurement error = 0.213 – 0.20 = 0.013

16. Understand Measurement Error / correction
• The results of calibration is sometimes expressed as a ‘correction’ or
‘measurement error’ on calibration certificate / report
• Example
• Correction is the value added algebraically to the uncorrected result of a
measurement to compensate for systematic error
• Thus, correction for the above; Correction = -0.002 mm
Nominal / true value of measurement 1.000 mm
Measured value 1.002 mm
Measurement error +0.002 mm

17. Do we need to apply the correction factor
into all our measurements ?
NO !! Only for readings where correction is higher than the
permitted customer specifications / tolerances
Some companies will use the Permissible Error, or Max Permissible
Error (MPE) to gage. Minimum permissible error use is 1/3 of the
spec tolerance. i.e. if the drawing stated 10cm +/- 0.01 cm, the MPE
= +/- 0.003cm

19. What are the alternative ways to apply
correction for errors as per the calibration
cert?
• Direct application using the correction value
• Using the nearest reported correction value in the cert
• Averaging between 2 correction factors
• Using linear interpolation to determine any value between 2
points

20. Example
1) Direct application
Let say you want to find the
correction factor for 20.
Correction = 20.000 – 19.955 = 0.045

21. Example
2) Using nearest reported
value
If we want to look for value
38, the nearest value is 40,
therefore we will use the 40
correction factor which is
0.089

22. Example
3) Averaging between 2
correlation factors
If we need correction for
value 25, so the value is
between 20 and 30
CF = (0.045+0.063)/2 = 0.054

23. Example
4) Using Linear Interpolation
Use the formula of y=mx +c
Imagine if we want to look for
CF for 37…..please work on the
calculation..
CF should be 0.0812

24. What is uncertainties (measurement
uncertainties)
• When engineers make a measurement or calculate some quantity from their data, they
generally assume that some exact or "true value" exists based on how they define what
is being measured (or calculated).
• Engineers reporting their results usually specify a range of values that they expect this
"true value" to fall within. The most common way to show the range of values is:
• Example if a measured value is 5.07mm, with a measurement uncertainties of +/- 0.02,
the actual value can be lies between 5.05 to 5.09
True measurement = observed measurement (result) ± U,
U = term for expanded uncertainty of the measurand and measurement result.

25. Confidence Level
• The confidence level tells you how sure
you can be
• The 95% confidence level means you can
be 95% certain
• Normal confidence level will be set at 95%
34.1%
13.6%
2.15% 34.1% 13.6% 2.15%
68.2%
95.4%
99.7%
+2s +3s
+1s
-2s -1s
-3s
2 sigma
K=2  confidence level of 95%

26. Types of uncertainties
• Uncertainties can arise from
– Measuring device
– Procedure of how you measure
– Observed quantity itself
• Systematic uncertainties
– Systematic uncertainties or systematic errors always bias results in one
specific direction, which can be inherent from the equipment.
• Random uncertainties
– Can be from a lot of factors, such as humans, method of use, environment,
etc

28. Understand calibration certificate
• What do you do when you receive the calibration
certificate?
• What are the key information in the certificate concern
you?
Just file it? Or show auditors that you have a cert? Looking at
the due dates only ?

29. What should a calibration certificate
include?
• Calibration certificate number
• Details of the laboratory tasked with calibration – SAMM logo, etc
• Customer info
• The equipment name and details (serial numbers)
• Evidence that the measurements are traceable
• Calibration results / correction factors, etc
• Calibration methods
• Calibration date
• Re-calibration due date
• Details on lab conditions where the calibration took place
• Name and signature of person performing the calibration
• Measurement uncertainty results
• Reference used

31. What to look for?
• Correction Factor
• Uncertainty

32. As Found / As Left
• As-Found: Indicates if the module is within specifications on arrival and before
performing the adjustment process.
• As-Left: Indicates if the device is within specifications after the adjustment and also if it
is likely to stay within specifications for another calibration interval.
• Check if value is within Upper and Lower Limit

33. Determine if your instrument is fit to be used
or not based on calibration cert
• Determine your process tolerance
• Check the specifications of the instrument in the user
manual
• Use the uncertainty results

34. Estimated based on Process Tolerance
• Example, if the error displayed in the calibration certification during the
calibration on the 20mm range is +0.06mm
• User has a process tolerance base don their process which is +/- 0.04mm, then
this means that it is already out of tolerance
• Unless, you can use it as it is, and inform operators of the correction factors

35. Check the specifications of the caliper in the
user manual, look for accuracy
specification / instrument tolerance
Based on this, you can use the TUR
method…

36. TUR – Test Uncertainty Ratio
• The Test Uncertainty Ratio (TUR) is a measure used in
calibration to determine the quality of a measurement
system. TUR is defined as the ratio of the accuracy (or
precision) of a measuring instrument to the uncertainty of
the calibration process.
• It provides a way to compare the potential measurement
error of a calibrated instrument to the accuracy of the
calibration standard used.
known as a Test Uncertainty Ratio (TUR)

37. TUR
• TUR =
TOLERANCE LIMIT
EXPANDED UNCERTAINTY
Typically, a TUR of at least 4:1 is considered acceptable in many industries,
meaning the calibration uncertainty should be four times smaller than the
tolerance of the UUT. A TUR below 4:1 may require additional
considerations or adjustments to ensure measurement accuracy.
Example: Instrument tolerance = +/- 0.1, expanded uncertainty = +/- 0.02
TUR = 0.1 / 0.02 = 5
The TUR in this example is 5:1. This means that the calibration uncertainty is five times
smaller than the instrument's tolerance, which is generally considered a good TUR,
ensuring that the measurement system is accurate.

38. The myth about calibration
• The presence of the calibration cert means that the
measuring instrument is reliable and can provide accurate
and reliable results
• After calibration, an instrument can be used with
confidence for the time specified by the calibration period
What do you think ?

39. Understand MSA
• Precision
 The degree of agreement (or
variability) between individual
measurements or test results from
measuring the same specimen(s)
• Accuracy
 The difference between the average
of the measurement error
distribution and the reference value
of the specimen measured

40. Accuracy…
• Error / Bias
• Linearity
• Stability
 Repeatability
 Reproducibility
Precision..

41. What is ISO17025
• ISO/IEC 17025 is the standard for general requirements for The Competence of
Calibration and Testing Laboratories
• Many countries have adopted ISO?IEC 17025 as the basis for establishing
quality systems and recognizing the competency of calibration laboratories by
3rd
party accreditation
• In Malaysia, the government has established National Laboratory Accreditation
Scheme on 15/8/90 which known as SAMM (Skim Akreditasi Makmal
Malaysia)

42. Accreditation illustration
Ministry of science, technology and environment
Department of Standard Malaysia (DSM)
Accreditation division
National Metrology
Center (NMC)
Calibration and testing lab
Company lab / user
equipment
To accredit
To certify
To accredit

43. Basic of requirements for calibration
• Reference / calibration standards and other instruments and
equipment
• Controlled environment conditions
• Competence of calibration lab personnel
• Traceability of reference / calibration standards
• Documentation
• Safeguard calibration integrity

44. Calibration status indicator
• To enable the user to know the equipment calibration status easily
• Types of calibration status indicator to be considered as follow:
– Self-adhesive sticker
– Tie-on label (for oily environment)
– Permanent market through engraving
• What sort of information should appear on the status indicator?

45. Safeguard Calibration integrity
• Access to adjustable devices on measuring equipment
whose setting affects validity of measurement results shall
be sealed or safeguarded to prevent tuning by unauthorised
personnel
• Common method: integrity seals, password for test
software, locked with key, etc (anything else?)

46. Before calibration…
• Check for any signs of outward damage,
– Chipped measuring faces
– Bent anvil (micrometer)
– Loose or missing parts
– Dirt or damaged track or gear
• All parts must be kept clean during calibration
• Wipe equipment clean with cloth and apply a drop of
fine oil to spindle (micrometer)

47. Documentation
• In any quality system, documentation
has very important role and therefore
proper care shall be taken for
documenting
– Calibration procedure
– Calibration results
– Calibration report
– Calibration certificate

48. Let’s connect !