Lovibond Tintometer MD 100 Manual De Instrucciones página 22

Preparation
1. Cleaning of vials:
As many household cleaners (e.g. dishwasher detergent) contain reducing
substances, this can lead to lower results with the determination of Chlorine.
To avoid measurement errors, the glassware used should be free of chlorine
consumption. To achieve this, all glassware should be placed in a sodium
hypochlorite solution (0.1 g/l) for one hour and then rinsed thoroughly with deionised
water.
2. For individual testing of free and total Chlorine, the use of different sets of glassware
is recommended (EN ISO 7393-2, 5.3)
3. The DPD colour development is carried out at a pH value of 6.2 to 6.5. The reagents
therefore contain a buffer for the pH adjustment. Strong alkaline or acidic water
samples must therefore be adjusted between pH 6 and pH 7 before the analysis (use
0.5 mol/l Sulphuric acid or 1 mol/l Sodium hydroxide).
EN Method Reference Book 1.0
Chlorine HR T / M103
EN
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