MEASUREMENT AND TESTING

TmeasurquMehrdad Kamali, CQP MCQI, MSc, explains why measurement andtesting is crucial for the quality control of products and services

As quality
professionals, howmuch do we needto know aboutmeasurement andtesting? There is plenty of publishedinformation on quality assurance,
quality control and quality systems;
however, no matter how robust ourquality assurance is, without solid
benchmarks for products and services,
we will not be able to accurately
measure our success. Even if thewhole process is left in the handsof a specialist, there will be a need

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for an overall understanding of themeasurement subject or control.
On writing this feature, I reflectedon the quote by Galileo Galilei:“Measure what can be measured,and make measurable what cannot
be measured”.

How to carry out themeasurement
After planning, measurement is a major
element of quality control. Any work is
still incomplete without planning, datacollection, data analysis and turning
this analysis into useful information.

When planning, we need to establish
why there is a need for measurement,
and what actions will follow based on
the measurement. It is only then that
we can logically start thinking about
how to measure.
The good news is that we don’t needto reinvent the wheel. The fundamental
requirements of testing and measuring
remain unchanged, and systems havebeen developed by thousands ofother organisations that have faced
similar issues. When we absolutely
must create a new way to measure,
we are in for some hard work. In that

MEASUREMENT AND TESTING

heement ofality
case, it is crucial to know exactly what
information we need, the correctdecision and what action will be taken
based on this information, then startcreating a measurement method.
To proceed, we need to answer somebasic questions:• Is it defective or non-defective?
• Go or no-go?
• Is the data attribute or discreet?
• What problems, errors, faults orrisks are there in the investigation
to minimise?
• How would you establish a (false)
alarm and its severity?
• How often should we measure?
• What equipment is required?
• What sample size is required?
• How will we analyse and present
the final information and to whom?
• When and where should it takeplace (in-line or off-line during theprocess or manufacture)?
• What degree of accuracy andprecision is required, and what is
the margin of error?
We also need to clearly define theresponsibilities for creating themeasurement plan and assuring itworks as intended. It is also important
to identify who will be managing theplan and inspection on an ongoingbasis, and what skills they need.
There is news of firms facing a talent
shortage. To start with, a quality

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MEASUREMENT AND TESTING
professional needs in-depth knowledgeof Geometric Dimensioning andTolerancing (a system for defining andcommunicating engineering tolerances),
as well as how this is incorporated into
quality assurance processes. As
measurement equipment is continually
improving and becoming moresophisticated, the challenge is training
and employing people who can workwith it and handle the data. This is amore pronounced issue in certain
industries than it is in others.
The essential requirement in allof the above is the traceability ofthe measurement results. This isdemonstrated through a documented
and unbroken chain of calibrations,each contributing to the measurement
uncertainty. It is up to the organisationthat performed the measurement
to prove through calibration
documents that traceability is linked
to organisations such as the National
Physical Laboratory (NPL) in the UK or
the National Institute of Standards andTechnology (NIST) in the US.

In search of certainty
Certainty is an elusive commodity.
An agile, data-driven organisation
can absorb, react to and mitigate theimpact of measurement data if it isaware of the level of uncertainty.
The adoption of digital technologies– often referred to as Industry 4.0 or
the fourth industrial revolution – withincompanies is helping them to reduce
their costs and stay ahead of theircompetition. To benefit fully, businesses
will need to step up all levels of theirtraining and data collection.
The application of data analytics
technology can provide the ability tointerrogate the collected data and tomaximise the precision and accuracyof information.
This information will assist inmonitoring product, productivity,
benchmarking, performance, improving
workflow, identifying and acting onunder/over-utilised equipment, waste
and preventive maintenance.
When collecting the data, it isimportant to know that a measurement
result is complete, and only when it
is accompanied by a statement of theassociated uncertainty. To understanduncertainty, please refer to A Beginner’s
Guide to Uncertainty of Measurement

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(bit.ly/3oph9UR) by Stephanie Bell,published by NPL.
Once we are happy with thedata, we then need to analyse andtransform it into information usablefor our purpose. John Wilder Tukey, anAmerican mathematician, describeddata analysis as: “Procedures foranalysing data, techniques forinterpreting the results of suchprocedures, ways of planning thegathering of data to make its analysis
easier, more precise or more accurate,and all the machinery and results of(mathematical) statistics, which apply
to analysing data.”
Data modelling and data visualisationsuch as formulas, tables, graphs, etc,
will assist in the communication.
It is also important to apply
techniques such as Measurement
System Analysis and Statistical Process
Control, which are employed to assistin accuracy, certainty and prevention of
defects getting into the next process.
Finally, like any other project, consider
the costs. Obviously, all the activities
discussed above have an associatedcost that needs to be considered
beforehand, to make sure that it does
not run over-budget.
All of the above is a consideration formeasuring a single parameter. A more
complex measure of product or service
requires further discussion.
In conclusion, this activity is acollaboration between the designers
who need to have an understandingof how each parameter is going to bemeasured, and the manufacturers,
service providers, suppliers and quality
personnel who need to understand theimportance of the parameter and aretrained in the equipment that is usedfor this purpose.
What has been examined here so far
is by no means the only consideration,
but it emphasises the fact that
although quality assurance and quality
systems are essential failure prevention
tools, quality control tools, methods
and techniques remain the proof ofthe pudding! There is so much more toknow and so much to learn.
We only need to look at recent
product failures from leadingorganisations to realise that data canbe used as evidence in courts when it
comes to customer satisfaction with all
its reputational outcome.

“An agile,data-driven
organisation canabsorb, react to andmitigate the impact
of measurement
data, if it is awareof the level ofuncertainty”