● provision of full documentation and traceability of results to recognized
reference materials through recorded identification;
● maintenance and calibration of instrumentation to manufacturers’ specifica-
tions;
● management and control of laboratory chemicals and other materials including
checks on quality;
● adequate training of laboratory personnel to ensure understanding and
competence;
● external verification of results wherever possible;
● accreditation of the laboratory by an independent organization.Quality assurance The overall management of an analytical laboratory should include the provision
of evidence and assurances that appropriate QC procedures for laboratory activ-
ities are being correctly implemented. Quality assurance(QA) is a managerial
responsibility that is designed to ensure that this is the case and to generate
confidence in the analytical results. Part of QA is to build confidence through the
laboratory participating in interlaboratory studieswhere several laboratories
analyze one or more identical homogeneous materials under specified condi-
tions. Proficiency testingis a particular type of study to assess the performance
of a laboratory or analyst relative to others, whilst method performance studies
and certification studiesare undertaken to check a particular analytical method
or reference material respectively. The results of such studies and their statistical
assessment enable the performances of individual participating laboratories to be
demonstrated and any deficiencies in methodology and the training of personnel
to be addressed.
Because of differences in the interpretation of the term quality, which can be
defined as fitness for purpose, QC and QA systems adopted by analyical labora-
tories in different industries and fields of activity can vary widely. For this
reason, defined quality standardshave been introduced by a number of organi-
zations throughout the world. Laboratories can design and implement their own
quality systems and apply to be inspected and accredited by the organization for
the standard most appropriate to their activity. A number of organizations that
offer accreditation suitable for analytical laboratories and their corresponding
quality standards are given in Table 1.Table 1. Accreditation organizations and their quality standards
Name of accreditation organization Quality standard
Organization for Economic Co-operation Good Laboratory Practice (GLP)
and Development (OECD)
The International Organization for ISO 9000 series of quality standards
Standardization (ISO) ISO Guide 25 general requirements for
competence of calibration and testing
laboratories
European Committee for Standardization EN 29000 series
(CEN) EN 45000 series
British Standards Institution (BSI) BS 5750 quality standard
BS 7500 series
National Measurement Accreditation NAMAS
Service (NAMAS)Accreditation
system
A6 – Quality in analytical laboratories 19