Endress+Hauser TOCII CA72TOC, Руководство по эксплуатации

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Installation TOCII CA72TOC
16 Hauser
Precautionary measures when working with chemicals
• Carefully read the "Material Safety Data Sheet" (MSDS) that is supplied with every chemical to
determine the hazards posed and what precautionary measures have to be taken. If you are not
sure what risks are associated with the chemical, please ask appropriately qualified experts.
• Never prepare chemicals on your own. You may need assistance in the event of an accident. For
this reason, always make sure that someone is close-by. Only prepare chemicals in a properly
equipped laboratory.
• When preparing chemicals always wear protective goggles, rubber gloves and a rubber apron. In
addition, wear a dust mask or face shield when working with fine-powder chemicals.
• Chemicals or solutions that are used with the analyzer (or another process analysis device) should
never be inhaled, tasted or swallowed.
• When preparing solutions, you must always label the containers appropriately, indicating the
contents and the date of preparation. Dispose of unlabeled or expired solutions in accordance with
local regulations and guidelines.
• Some chemicals are very reactive when combined with other substances or dissolved in water
and cause explosions, fire or heat to occur, or dangerous gases, foams or sprays to be released.
Avoid the risk of dangerous accidents occurring: If you do not know how certain chemicals react,
make sure you do not mix them with other substances. Never mix chemicals that are known to
react severely.
Reagent quality
!
Note!
Reagent quality can affect the accuracy of measurements. For this reason, follow the steps outlined
below to ensure reagent quality.
• For 10, 100, and 500 mg/l units, use the best grade of reagents. For 1,000, 5,000, and
10,000 mg/l units, ordinary commercial grade acids and persulfate are suitable. For the KHP
calibration standard, use reagent grade or better for all units. For the 1,000, 5,000 and
10,000 mg/l units, you can experiment with quality once you have established repeatability, and
as long as the results are not affected. Lower grades of acid and persulfate may be acceptable.
• Rinse all glassware and plastic containers thoroughly with deionized water. For best results,
acid-wash and rinse them again before use.
• Use good scales and weigh the standard as accurately as possible before mixing. Keep containers
closed to prevent contamination and deterioration.
• Accurate preparation of the calibration standard is essential for accurate calibration of the
analyzer. Inaccurate preparation of the standard will result in an erroneous calibration, which in
turn will yield worthless results.
• The KHP calibration standards for 10 and 100 mg/l deteriorate rapidly in solution. Keep
containers closed when not in use, and store in a cool place (such as a refrigerator). Heat and
exposure to air can ruin sensitive solutions quickly.
Preparing potassium hydrogen phthalate
"
Caution!
Potassium hydrogen phthalate (KHP) can irritate the skin and cause problems with the eyes or
respiratory channel. Do not inhale the powder and do not attempt to ever swallow any of the
solution prepared.
Shelf life : Relatively stable, depending on the concentration. (Stability decreases with decreasing
concentration; refrigeration is recommended.)
Concentrations: Depends on the application.