User Guide

107
• Remove the cuvet.
• Add the content of one packet of
HI 93707 reagent. Replace the
cap and shake gently for about
15 seconds.
• Reinsert the cuvet into the instrument.
• Press TIMER and the display will show the countdown prior to the
measurement or, alternatively, wait for 6 minutes and press READ
DIRECT. In both cases “SIP” will blink during measurement.
• The instrument directly displays concentration in mg/L of nitrite
nitrogen.
• To convert the NO
2
–
-N concentration to the nitrite ion concentra-
tion (NO
2
–
), multiply the reading by factor of 3.29.
• To convert the NO
2
–
-N concentration to sodium nitrite concentra-
tion (NaNO
2
), multiply the reading by factor of 4.93.
INTERFERENCES
Interference may be caused by the following ions:
ferrous, ferric, cupric, mercurous, silver, antimonious, bismuth, auric,
lead, metavanadate and chloroplatinate.
Strongly reducing and oxidizing reagents.
High levels of nitrate (above 100 mg/L) could yield falsely high
readings due to a minute amount of reduction to nitrite that could
occur at these levels.
Nitrite LR