LaMotte CORROSION CONTROL Test Kit - Manual (Page 13)

REC OM MENDED STAN DARD IZA TION PRAC TICES
The Corrosion Control Kit tests for Alkalinity, Calcium Hardness,
Phosphate, pH, and TDS. This outfit was designed specifically for field
testing purposes. In order to check the performance and accuracy of the
equipment it is recommended that the equipment be checked against
reference standards. Routine performance checks will enable the operator
to keep track of the accuracy and be able to address any problems in the
testing methods or the equipment, and guarantee that the performance
specifications are being achieved.
The age of the reagents can be determined from the lot number, a 6 or 7
digit number found on the reagent bottle. Only the first three digits are
important. The first two digits refer to the week of the year. The third digit
refers to the last digit of the year. For example: 061 would refer to the sixth
week of 2001.
To determine the performance, check for Alkalinity, Calcium Hardness,
and Phosphate. Concentrated standard solutions are available for each
analyte. The operator dilutes the concentrate using good laboratory
practices to a level which can be correctly tested by the method provided.
The concentrated standards are made according to APHA or EPA
specifications, and use reagent grade chemicals to provide the necessary
analyte in a stabilized chemical form.
The electrometric methods for measuring pH and TDS are subjected to the
same type of performance test. The pH Tester is checked against a standard
buffer solution that is provided with the kit. This buffer is prepared from
salts that are traceable to NIST buffers. The TDS solutions are also
prepared from salts that are traceable to NIST standards.
It is a good practice and highly recommended that the operator keep a
journal or log of all performance test results: dates tested, and age of all the
reagents used in the tests. See suggested Log Form.
To conduct performance tests on the equipment and the methods based on
the reference standards, the following recommended procedures are
provided:
ALKALINITY STANDARD · CODE 5168
Fill 100 mL volumetric flask to 1
2
volume with Deionized water. Use pipet
to dispense 1.0 mL of standard into flask. Dilute to volume and mix.
Diluted standard = 100 ppm Total Alkalinity
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