This booklet describes the basics of pH measurement.
Key information is provided on pH theory, how a pH electrode works,
calibration and maintenance of pH electrodes, choosing the proper
pH electrode for your application, standard solutions and temperature
influence on pH.
This booklet describes the basics of conductivity
measurement.
The scope of this booklet is to discuss the theoretical aspects of
conductivity, the factors that influence the reliability of the measurement,
and the techniques. Sections covering the applications, rules for
reliable measurements and frequently asked questions have been included
to make this a comprehensive review of the importance of conductivity
measurements.
The importance of traceability in relation
to pH and conductivity
For laboratories concerned by certification or
accreditation, the use of certified reference materials traceable
to their national standards is highly recommended.
This article contains advice on how to be sure of the quality and
traceability of your pH and conductivity measurements.
Conductivity measurement on pure water according
to the recommendations of the USP Pharmacopoeia USP24-NF19
Pharmaceutical laboratories working in the US
market are obliged to respect the regulations set down by the US Pharmacopoeia.
The 5th supplement of USP24-NF19 lays down the rules for checking
the quality of pure or fully deionised water used for the production
of injection products. These rules are not particularly easy to implement
and the expertise of a manufacturer of analytical instruments like
Radiometer Analytical is a crucial aid.
Radiometer Analytical is part of the Hach Lange
group and their Calibration Laboratory, located in Berlin, is accredited
for the calibration of certified pH and conductivity standards by
DKD, the German national accreditation authority. This accreditation
(No. DKD-K-47901) is recognised in more than 35 countries and covers
the calibration of our ranges of certified
standard solutions: IUPAC standards for pH and OIML standards
for conductivity.
Certified ISO9001:1994 since January 1998,
Radiometer Analytical received ISO 9001:2000 Certification by LLoyd's
Register Quality Assurance in November 2002.
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