IJCA - Volume 2 - Flipbook - Page 59
2023 | Volume 2, Issue 1
Risk Unlocks Opportunity … but Diligence Is
Key to Avoiding Potential Impacts
When a laboratory takes risks, this also creates
an opportunity to expand the scope of activities,
addressing new customers, new technologies, and
other opportunities to meet customer needs. (Note 2
of Clause 8.5.2.)
But while taking risks, laboratories should maintain
compliance with all other requirements of ISO/IEC
17025 (e.g., calibration of measuring equipment,
purity of chemicals and reagents used, traceability to
SI units, personnel training, etc.). Quality assurance
activities such as intralaboratory comparison, as well
as parallel and rechecking of tested samples as blind
samples should be carried out to build and increase
confidence.
The note under Clause 8.5.2 seems to indicate it is
not mandatory for a laboratory to always undertake
risks. However, if the laboratory is willing to take
risks (aka challenges), it should be able to assess
the potential impact of the risk on the validity
of laboratory results and take care to prevent or
reduce undesired impacts and potential failures
in the laboratory activities.The risks taken should
be identifiable and measurable in order to identify
potential impacts.
In the following, the author presents a few examples
in his experience, just merely to illustrate the concept
of risk and opportunity.
A customer was using Muriate of Potash procured
from a supplier, and he suspected the presence of
ammonia. He approached the laboratory to ascertain
and determine the ammonia content. This request
was unusual since no one expected to test ammonia
in Muriate of Potash and no standard refers to such
a test. The laboratory worked out a method and
confirmed the presence of ammonium salt. Since
the method involved the distillation of ammonia and
then Nessler’s method of determination, which are
established methods, the laboratory was confident
in its results. The laboratory was sure that the risk
levels were very low or practically nil. The supplier,
who never believed there could be ammonia in
his product, initially questioned the results. But
the laboratory could demonstrate the same to his
satisfaction. The laboratory won a new customer,
which further extended to others in the field, creating
more opportunities for the laboratory.
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While working in the zinc-lead industry, a sudden
requirement came up because of some process
problem to estimate/determine the unburnt carbon
levels in Waelz kiln slag. The laboratory was aware
the slag contains constituents such as sulphides,
so direct ignition was ruled out. It worked out a
method wherein the sulphides in the sample were
first decomposed using dilute acids (combination of
hydrochloric and nitric acids) at low temperatures,
and then the dried residue was re-ignited and the
carbon content was arrived at based on the final loss
of ignition. In this case, certain risks were taken by
way of assuming that all sulphides are such, which
get broken down with dilute acid digestion, and that
carbon remains unaffected at that stage. Based on
the inputs of the raw material, the laboratory was
confident the slag would not contain such sulphides
(e.g., chalcopyrite), which do not decompose with
dilute acids. Based on the chemical behavior of
carbon, the laboratory was confident the carbon
was not affected by dilute acids at the temperatures
they were using. The laboratory discussed these
risks with the plant personnel and the management.
After further studies of the process behavior,
the plant personnel on their own confirmed the
laboratory findings seemed to be in order. Plant
and management personnel were happy that the
laboratory could offer some useful information,
which helped in controlling/improving the process.
Another example centers on the deviation of a
standard method. When the author joined the
process lab, the lead refinery samples were being
tested by atomic absorption spectroscopy. The
refinery plant was complaining that the feedback
from the laboratory was slow in the copper removal
stage, because a lot of fuel was wasted keeping the
kettle hot and also there was a possible reversion of
copper from dross back to lead metal while waiting
for the result. The first stage of lead refining involved
copper removal as copper dross. The refinery plant
was not interested in the exact values of copper
in the copper drossing stage and once the copper
is confirmed to have come down to less than 100
gpt (grams per metric ton or parts per million), the
process would proceed for the next stage of refining.
To hasten process feedback, instead of running
copper standards each time along with samples
and then arriving at the exact values, the laboratory
worked out a reference lead sample with an
established value of 90 gpt copper. The laboratory
