Low-level ammonia nitrogen may be naturally present in water as a result of the biological decay of plant and animal matter. Higher concentrations in surface waters can indicate contamination from waste treatment facilities, raw sewage, industrial effluents (particularly from petroleum refineries), or fertilizer runoff. Excessive ammonia concentrations are toxic to aquatic life.
The Hydroxybenzyl Alcohol (HBA) Method
In the ammonia test method that employs the Hydroxybenzyl Alcohol chemistry, free ammonia reacts with hypochlorite to form monochloramine. Monochloramine reacts with HBA, in the presence of sodium nitroferricyanide, to form a green colored complex. This test method measures the sum of free ammonia and monochloramine. Results are expressed in ppm (mg/L) ammonia-nitrogen, NH3-N.
The Hydroxybenzyl Alcohol Method offers sensitivity similar to the Nesslerization Method and there is no generation of mercury-containing waste.
Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Comparator, Stabilizer Solution, Catalyzer Solution, Activator Solution, 25 mL sample cup, 3 mL syringe, and instructions.
Krom, Michael D. Spectrophotometric Determination of Ammonia: A Study of a Modified Berthelot Reduction Using Salicylate and Dichloroisocyanurate, The Analyst, V105, pp. 305-316, 1980.
Range: 0-4 & 0-80 ppm
MDL: 0.125 ppm
Method: Hydroxybenzyl Alcohol (HBA)
Shelf life = 8 months