70
6 Reference Materials in Chemical Measurements
6.2 Production of Reference Materials
In between experts dealing with RMs, discussions are also conducted on the forthcoming document that is to include guidelines for manufacturers and users of the
RMs located on the lowest level of the metrological hierarchy, such that they can
be used in the laboratory in routine measurements of quality control. In practice,
various terms, such as quality control materials’ or ‘laboratory reference materials’
are used. But regardless of the name used, it is important to establish widely accepted
requirements for materials with the lowest metrological hierarchy, fulfilling at the
same time an important role in the daily quality control to the economically justified
level.
It is worth noting that while the number of documents related to RMs is not large,
they include very different areas: from production to their use in laboratory practice.
For the analyst, of course, the most important are the requirements for the proper
use of RMs. However, one should also be aware of what the requirements of manufacturers of these materials are, where the results of these requirements are derived
from and what the impact is of the manufacturing process on the metrological value
of the product. From the user’s perspective, an important requirement with regard
to the chemical standards and RMs are the competences of the manufacturer. RMs
should assure have, where possible, a traceability link to the units of measurement SI
or CRMs. It is worth remembering that the production of chemical RMs is a complex
process, involving primarily the proper preparation of the material to demonstrate its
homogeneity, stability, and the characteristics of accuracy and measurement traceability of the reference value. It is also worth noting the problems related to the
acquisition of a suitable material; for example, the contents of medicinal substances
in plants vary significantly depending on the location and time of harvest; and animal
tissues, for example, are difficult to obtain.
The production of matrix RMs is a highly specialized activity. The production of
a single type of material requires huge investment, and the income from the sale of
the material rarely fully covers the cost of its production, certification, and storage.
The process of planning the processing of the material, its production, certification,
and how to determine the conditions of transport of the material to the customers and
how it is stored is extremely important. Problems related to the production and certification of RMs are not always known to their users. But it is worth knowing, at least
in outline, what difficulties the producers must cope with, since this will allow for
a better understanding of the high costs and the proper use of materials in chemical
measurements. The manufacturing process involves many steps: acquisition of a substantial portion, often several hundred kilograms of the material; crushing; grinding;
freeze-drying; and sterilization. The manufacturer of the material should guarantee
its stability within the validity period, and this requires systematic monitoring of the
selected property at the time of selling. The high cost of production of RM, however,
is fully justified. The production itself requires preparation of appropriate production lines and modern equipment (sometimes it is necessary to prepare equipment
designed specifically and exclusively to produce the type of RM in question) and
6 Reference Materials in Chemical Measurements
6.2 Production of Reference Materials
In between experts dealing with RMs, discussions are also conducted on the forthcoming document that is to include guidelines for manufacturers and users of the
RMs located on the lowest level of the metrological hierarchy, such that they can
be used in the laboratory in routine measurements of quality control. In practice,
various terms, such as quality control materials’ or ‘laboratory reference materials’
are used. But regardless of the name used, it is important to establish widely accepted
requirements for materials with the lowest metrological hierarchy, fulfilling at the
same time an important role in the daily quality control to the economically justified
level.
It is worth noting that while the number of documents related to RMs is not large,
they include very different areas: from production to their use in laboratory practice.
For the analyst, of course, the most important are the requirements for the proper
use of RMs. However, one should also be aware of what the requirements of manufacturers of these materials are, where the results of these requirements are derived
from and what the impact is of the manufacturing process on the metrological value
of the product. From the user’s perspective, an important requirement with regard
to the chemical standards and RMs are the competences of the manufacturer. RMs
should assure have, where possible, a traceability link to the units of measurement SI
or CRMs. It is worth remembering that the production of chemical RMs is a complex
process, involving primarily the proper preparation of the material to demonstrate its
homogeneity, stability, and the characteristics of accuracy and measurement traceability of the reference value. It is also worth noting the problems related to the
acquisition of a suitable material; for example, the contents of medicinal substances
in plants vary significantly depending on the location and time of harvest; and animal
tissues, for example, are difficult to obtain.
The production of matrix RMs is a highly specialized activity. The production of
a single type of material requires huge investment, and the income from the sale of
the material rarely fully covers the cost of its production, certification, and storage.
The process of planning the processing of the material, its production, certification,
and how to determine the conditions of transport of the material to the customers and
how it is stored is extremely important. Problems related to the production and certification of RMs are not always known to their users. But it is worth knowing, at least
in outline, what difficulties the producers must cope with, since this will allow for
a better understanding of the high costs and the proper use of materials in chemical
measurements. The manufacturing process involves many steps: acquisition of a substantial portion, often several hundred kilograms of the material; crushing; grinding;
freeze-drying; and sterilization. The manufacturer of the material should guarantee
its stability within the validity period, and this requires systematic monitoring of the
selected property at the time of selling. The high cost of production of RM, however,
is fully justified. The production itself requires preparation of appropriate production lines and modern equipment (sometimes it is necessary to prepare equipment
designed specifically and exclusively to produce the type of RM in question) and