Disampaikan pada Bimbingan Teknis Pengelolaan Laboratorium Dan Standar Ukuran Di Bidang Metrologi Legal di Hotel Grand Zuri Yogyakarta tanggal 8 Mei 2014

1. PELAKSANAAN CEK ANTARA STANDAR UKURAN
LABORATORIUM MASSA DI BSML REGIONAL II
Disampaikan oleh Arif Nurjaya, ST
Bimbingan Teknis Pengelolaan Laboratorium Dan Standar Ukuran Di Bidang Metrologi Legal
Hotel Grand Zuri Malioboro Yogyakarta

2. The Ministry of Trade of the Republic of Indonesia
Check standard is a standard that is used as part of
measurement assurance program to provide check on the
standard and process to ensure that the standards,
measurement results, and measurement processes are
within acceptable statistical limits.
–KAN G-06 Guide On Measurement Assurance

3. E 2 F 1 Artifact
CHECK STANDARD
Calibration
?
Check standard

4. The Ministry of Trade of the Republic of Indonesia
The concept of statistical process control is based on
comparing how measurement process is performing today
(often a single measurement) to how it has performed in
the best (a database of measurement results).
–KAN G-06 Guide On Measurement Assurance

5. The Ministry of Trade of the Republic of Indonesia
STATISTICAL PROCESS CONTROL
Today The Best
5
(initial data)

6. 123.00O
N
O
FF
AT Standar
AT Dikalibrasi 2010321
A B B A
1 DATA =
A B B A
A B B A
A B B A
Massa
Konv.
1 SERI

7. The Ministry of Trade of the Republic of Indonesia
Control chart is a graphical tool used to visualize data
when monitoring, evaluating and improving a
measurement process
–KAN G-06 Guide On Measurement Assurance

8. The Ministry of Trade of the Republic of Indonesia
CONTROL CHART
8
Data 1
Data 2
Data 3
Data 4
Data 5
Data 6
Data 7
Data 8
Data 9
Data 10
10 is good number of data points to use as the baseline for our
initial control measurements. Be sure to gather data over a period
of time, with not more than 1 measurement from the same day.
MEAN
DEVIATION
Statistical Warning Limits
Statistical Action Limits
UWL
LWL
= mean + (2 x deviation)
= mean - (2 x deviation)
Upper
Lower
UAL
LAL
= mean + (3 x deviation)
= mean - (3 x deviation)
Upper
Lower
The Best
(initial data)

9. The Ministry of Trade of the Republic of Indonesia
CHECK STANDARD
9
Description : 3 point control chart
Balance used : XP26C / 0.001 mg
Load : 0.002 g
Unit : g
Check Standar : F1 OIML class
Serial Number : 15885
Date Data Correction Mean Std Dev
LIMIT
UWL LWL UAL LAL
4-Feb-13 0.0020017 0.0017
0.00005 0.0010
0.0021 -0.0020 0.0031 -0.0030
5-Feb-13 0.0020007 0.0007
6-Feb-13 0.0020002 0.0002
7-Feb-13 0.0020012 0.0012
8-Feb-13 0.0019987 -0.0013
9-Feb-13 0.0019997 -0.0003
10-Feb-13 0.0019987 -0.0013
11-Feb-13 0.0020007 0.0007
12-Feb-13 0.0019992 -0.0008
13-Feb-13 0.0019997 -0.0003
7-Jul-13 0.0020035 0.0035
0.00157 0.00258-Jul-13 0.0020025 0.0025
9-Jul-13 0.0019987 -0.0013

10. The Ministry of Trade of the Republic of Indonesia
CHECK STANDARD
10
Description : 3 point control chart
Balance used : XP26C / 0.001 mg
Load : 0.002 g
Unit : g
Check Standar : F1 OIML class
Serial Number : 15885
MassCorrection(mg)
Control Chart
0,004
0,003
0,002
0,001
0,000
-0,001
-0,002
-0,003
-0,004
4-13 Feb 2013 Date 7-9 Juli 2013
UWL
LWL
UAL
LWL

11. The Ministry of Trade of the Republic of Indonesia
Out of Control? What next???
− Recalibration of the standard
− Validate calculation software
− Validate check standard calculation
− Obtain service or repair for balance
− Get new staff trained as soon as possible
− Fix environmental control as soon as possible

12. The Ministry of Trade of the Republic of Indonesia
STATISTICAL EVALUATION
Today The Best
Deviation
Mean
Deviation
Mean
12
t - test
F - test
(initial data)

13. The Ministry of Trade of the Republic of Indonesia
F – test
F – test is used to evaluate two processes have equivalent standard
deviations
𝐹𝑣𝑎𝑙𝑢𝑒 =
𝑠 𝑜𝑙𝑑
2
𝑠 𝑛𝑒𝑤
2
Our measurement system is considered to be “out of control” if we meet the
following conditions:
𝐹𝑣𝑎𝑙𝑢𝑒 > 𝐹∝,𝑣 𝑛𝑒𝑤,𝑣 𝑜𝑙𝑑
; if 𝑠 𝑜𝑙𝑑
2
>𝑠 𝑛𝑒𝑤
2
𝐹𝑣𝑎𝑙𝑢𝑒 < 𝐹1−∝,𝑣 𝑛𝑒𝑤,𝑣 𝑜𝑙𝑑
; if 𝑠 𝑜𝑙𝑑
2
<𝑠 𝑛𝑒𝑤
2
Possible action steps:
− Obtain service or repair for balance
− Get new staff trained as soon as possible
− Fix environmental control as soon as possible
13

14. The Ministry of Trade of the Republic of Indonesia
F – test
14
OIML R111-1:2004 Annex D

15. The Ministry of Trade of the Republic of Indonesia
t - test
t – test is used to evaluate the means of two processes
𝑡 𝑣𝑎𝑙𝑢𝑒 =
𝑥 𝑜𝑙𝑑 − 𝑥 𝑛𝑒𝑤
𝑠 𝑜𝑙𝑑
2
𝑛 𝑜𝑙𝑑
+
𝑠 𝑛𝑒𝑤
2
𝑛 𝑛𝑒𝑤
Our measurement system is considered to be “out of control” if we meet the
collowing conditions:
𝑡 𝑣𝑎𝑙𝑢𝑒 < 𝑡 𝑐𝑟𝑖𝑡𝑖𝑐𝑎𝑙 ; 𝑣 =
𝑠 𝑜𝑙𝑑
2
𝑛 𝑜𝑙𝑑
+
𝑠 𝑛𝑒𝑤
2
𝑛 𝑛𝑒𝑤
2
𝑠 𝑜𝑙𝑑
2
𝑛 𝑜𝑙𝑑
𝑛 𝑜𝑙𝑑−1
+
𝑠 𝑛𝑒𝑤
2
𝑛 𝑛𝑒𝑤
𝑛 𝑛𝑒𝑤−1
Possible action steps:
− Recalibration or get maintenance of the standard
− Validate calculation software
− Validate check standard calculation
15

16. The Ministry of Trade of the Republic of Indonesia
t - test
16
OIML R111-1:2004 Annex D

17. The Ministry of Trade of the Republic of Indonesia
ANALYZE DATA
17
Control
Chart
• Process degradation
• Process improvement
• Process compared to
specification / tolerances
• Shift in values of standard
• Drift of values of standard
• Outliers
• Possible assignable
causes
• Possible action steps

18. 18
PROCESS IMPROVEMENT
We obtained service for your balance
We have a new calibration officer who has many years of previous experience
Our environmental controls were repaired or improved
We have been practicing in balance operation

19. 19
SHIFT IN VALUES OF STANDARD
Our standard is damage
Our check standard is damage
We are using calculation software
that has not been validated
We have errors in entering data
Our equation for the correction due to environmental
condition were drifted and correction changed
Our standard was recalibrated and a new value was
assigned without starting a new control chart

20. 20
DRIFT OF VALUES OF STANDARD
Our working standard worn from use
Our check standard getting dirty
Our standards are not stable enough for this process

21. 21
OUTLIERS
Balance not exercised normally / properly
We do not allow adequate thermal equilibrium to the standard prior to begin calibration
We have data entry error or miscalculation
Our environmental system is out of control
Our standard was recently damaged

22. 22
PROCESS DEGRADATION
Our balance need service
We have calibration officer in the laboratory who needs training
Our environmental controls stopped working properly

23. 23
PROCESS COMPARED TO SPECIFICATION / TOLERANCES
Our process is not achieving the requirements needed to meet the tolerances
because our balances has degraded and can not reach its normal performance

24. The Ministry of Trade of the Republic of Indonesia
Laboratorium
Volume
Laboratorium
Suhu
Laboratorium
Gaya dan
Tekanan
Laboratorium
Massa
Laboratorium
Panjang
24

25. a r i f. n u r j a y a @ k e m e n d a g . g o . i d
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