YSI 9300 Photometer - Manual (Page 56)

Test Procedure
1 Fill test tube with sample to the 10 ml mark.
2 Add one Acidifying GP tablet and one Chlorine HR tablet. Crush tablets and
mix to dissolve. Allow any undissolved particles to settle.
3 Select Phot 9 on photometer.
4 Take photometer reading in usual manner (see photometer instructions).
5 The result is displayed as mg/l Cl.
Note: For precise determination of lower levels of chlorine, up to 5 mg/l, the YSI
Chlorine (DPD) method should be used.
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