Objective To use flow injection method and continuous flow method to determine ammonia nitrogen in drinking water and source water, and to evaluate the relevant technical parameters, and to analyze the reliability of the two techniques in the determination of ammonia nitrogen in drinking water and source water.

Methods The ammonia nitrogen in drinking water and source water was measured by flow injection instrument and continuous flow instrument respectively, and the measurement range, lowest detection quality concentration, precision, recovery rate and other relevant parameters were evaluated; the result were compared with the actual water samples determined by the current national standard method; at the same time, the relevant interference factors were analyzed.

Results Flow injection method and continuous flow method were used in the range from 0.02 mg/L to 2.00 mg/L, the determination of ammonia and nitrogen in drinking water and source water has a good linear relationship, the correlation coefficient (r) were greater than 0.999; the minimum detection mass concentration were less than 0.02 mg/L; the relative standard deviation were less than 2%; the recovery rate of standard addition ranged from 86.0% to 99.6%;The measured values of certified reference materials are within the uncertainty range of the certified reference materials; compared with the national standard method, the actual value was within the uncertainty range of the standard substance There was no significant difference in the determination result of water samples by t-test.

Conclusion Flow injection method and continuous flow method could be used for the determination of ammonia and nitrogen in drinking water and source water.