YSI 9300 Photometer - Manual (Page 84)

Test Procedure
1 Fill round test tube with sample to the 10 ml mark.
2 Add one Nitricol tablet, crush and mix to dissolve.
3 Stand for 10 minutes to allow full color development.
4 Select Phot 24 on photometer for result as mg/l N, or Phot 64 for result as
mg/l NO
2
).
5 Take photometer reading in usual manner (see photometer instructions).
To convert from mg/l N to mg/l NO
2
multiply result by 3.3.
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