measurement challenges in testing and …...3.3 estimation and use of measurement uncertainty....

MEASUREMENT CHALLENGES IN TESTING AND

CALIBRATIONS LABORATORIES

DRC CASE

By

ASCOLAB TEAMMichee Mansoj-MUMI Laboratory Manager

Flory Ngindu-OCC Metrology Laboratory Head office

Didier Makonga-SSM Technical Director

Victor Kanama-ASCOLAB Chairperson

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SAINT GEORGES HOTEL, 01 AUGUST 2017

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CONTENT

1.BACKGROUND2. INTRODUCTION3. PERFORMANCE OF PROBLEMS4. SUGGESTIONS5. CONCLUSION


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1. BACKGROUND


What means measurement ?

What are the measurement requirements?

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1. BACKGROUND


What means measurement ?

Measurement (2.1) - process of experimentally obtaining one or

more quantity values that can reasonably be attributed to a

quantity. Measurement implies comparison of quantities or

counting of entities. Measurement presupposes a description of

the quantity commensurate with the intended use of a

measurement result, a measurement procedure, and a

calibrated measuring system operating according to the specified

measurement procedure, including the measurement conditions

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1. BACKGROUND


What are the measurement requirements?

Among these requirements, we were interested in metrological

traceability.

Metrological traceability (2.41) - property of a measurement

result whereby the result can be related to a reference through a

documented unbroken chain of calibrations, each contributing to

the measurement uncertainty.

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1. BACKGROUND


Testing or calibration results requires a measurement

process that contribute to the quality of the result.

This measurement process requires also a metrological

traceability to insure the quality of measurement.

Our laboratories are confronted with the problem of

metrological traceability and in general the problem of

quality assurance of testing or calibration result.

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1. INTRODUCTION


The quality assurance of the calibration or testing

results passes among others through the metrological

traceability without witch quality assurance results

cannot be achieved.

This problem of metrological traceability is faced in

terms of:

3.1 The existing laboratory does not cover all the

needs of member laboratories in metrological

traceability and high cost of calibrations when

addressing competent laboratories abroad;

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3. PERFORMANCE OF PROBLEMS


3.2 Lack of the Certified Reference Materials (CRM).

The use of the Certified Reference Materials is

important to control the analysis results.

Unfortunately, many laboratories do not understand

the importance of the CRM and do not use them

most the time.

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3.3 Estimation and use of measurement uncertainty.

Estimation of measurement uncertainty is a

requirement in ISO/IEC standards for accreditation:

- ISO 15189 (clause 5.6.2) and

- ISO/CEI 17025 : 2005 (clauses 5.4.6.1 and 5.4.6.2)

5.10.3.1 to mention the uncertainty on the results

report.

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But many laboratories do not understand what is the

measurement uncertainty, even how or why to

calculate the measurement uncertainty associated to

their analysis results.

Measurement uncertainty and PT?

Measurement uncertainty and conformity declaration?

Identification and analysis of sources of uncertainty?

Quantification of uncertainty elements.

Calculation of uncertainty?

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This problem is compounded by:

(a) Validation of analysis methods

The validation of analysis method is not made before

using an alternative method when the standardized

method is not available. It is a real problem for many

laboratories to understand how to validate an analysis

method.

(b) Participation in Proficiency Testing scheme Program

Many Laboratories participate in PT scheme without

understanding its real importance and are not able to

analyze and to manipulate to one’s advantage of the

PT results.12



(c) Maintenance of equipment

Routine and preventive maintenance of equipment is

still a challenge. When an equipment is damaged, it is

a problem to fix it maybe for the lack of spare parts.

Also when the program of maintenance is not

performed, it is a risk for the quality of labs results;

(d) Control chart is still an unknown concept or not

well known by many labs. When it is used by same

to ensure the quality of their results , it is wrongly;

(e) The educational program in secondary and

university doesn’t include quality concept in general

and metrological traceability in particular.

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ASCOLAB suggests the following actions to meet

the measurement challenges in the laboratories:

- To strengthen the capabilities of the national

metrology laboratory so that he can play his role to

provide a wide range of metrological traceability;

- To encourage the establishment of private calibration

laboratories;

- To create opportunities for laboratories to produce

certified reference materials;

- To insert quality concept in the educational program;

- To organize the awareness workshop for our members

in the use of reference materials and analysis of PT

scheme results. 14

4. SUGGESTIONS


ASCOLAB is concerned by its mission to participate in

the promotion of the laboratories of our members for

the good quality of the results of calibration and

testing.

We wish a welcome to all partners interested in this

issue to support our members for the best quality of

life.

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5. CONCLUSION


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ASCOLAB

BUILD A QUALITY OF LIFE


measurement challenges in testing and …...3.3 estimation and use of measurement uncertainty....

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