LaMotte AMMONIA NITROGEN TEST KIT SAN - Manual (Page 2)

PRO CE DURE
1. Fill test tube (0230) to 5 mL line with sample water.
2. Use the plastic pipet (0354) to add 1 mL of *Citrate Buffer (7453).
3. Use the 0.15 g spoon (0727) to add one level measure of *Salicylate
Reagent (7454). Cap and mix. Wait one minute. Solution will turn
yellow.
4. Use the 0.1 g spoon (0699) to add one level measure of *Isocyanurate
Reagent Powder (7455). Cap and shake vigorously until all solid has
dissolved. Wait at least 12 minutes until green color develops.
5. Place test tube into the Ammonia Nitrogen Comparator (7452).
Match sample color with a color standard. Record as ppm
Ammonia-Nitrogen. If the sample color is between two standards,
the midpoint between the standards is taken as the result.
6. If sample is darker than the 1.0 ppm color standard, the sample must
be diluted and retested. Use the 0.5 mL pipet (0353) to add 0.5 mL of
sample water to test tube. Dilute to 5 mL line with distilled or
deionized water. Follow Steps 2-5. Multiply reading by 10. Record as
ppm Ammonia Nitrogen.
7. To express results as Unionized Ammonia (NH
3
):
Unionized Ammonia (NH
3
) =
ppm Ammonia Nitrogen (NH
3
-N) x 1.2
To express results as Ionized Ammonia (NH
4
+
):
Ionized Ammonia (NH
4
+ ) =
ppm Ammonia Nitrogen (NH
3
-N) x 1.3
Ammonia in water occurs in two forms: toxic unionized ammonia (NH
3
)
and the relatively non-toxic form, ammonium ion (NH
4
+
). This test
method measures both forms as ammonia-nitrogen (NH
3
-N) to give the
total ammonia-nitrogen concentration in water. The actual proportion of
each compound depends on temperature, salinity, and pH. A greater
concentration of unionized ammonia is present when the pH value and
salinity increase.
1. Consult the table below to find the percentage that corresponds to
the temperature, pH and salinity of the sample.
2. To express the test result as ppm Unionized Ammonia Nitrogen
(NH
3
-N), multiply the total ammonia-nitrogen test result by the
percentage from the table.
3. To express the test result as ppm Ionized Ammonia Nitrogen
(NH
4
+
-N), subtract the unionized ammonia nitrogen from the total
ammonia-nitrogen.