The Ministry of Health has revised the procedure for the approval of new test(s) used for the determination of compliance with the Drinking-water Standards for New Zealand (DWSNZ).
Laboratories conducting tests for drinking-water compliance are either accredited by International Accreditation New Zealand (IANZ) or are recognised Level 2 laboratories. Laboratories conducting chemical tests may use the test methods for which they have been assessed by IANZ and found to be competent to perform, for the above compliance testing. Laboratories conducting bacteriological tests for drinking-water compliance need to use a referee method specified in the DWSNZ, or a method that has been calibrated against a referee method.
For new presence/absence bacteriological test methods, refer to The Ministry of Health procedure for approval of new test methods for bacteriological compliance testing of drinking-water samples using presence/absence methods (doc, 31.5 KB)
For numeric methods, refer to NIWA’s 2007 report to the Ministry of Health: Equivalence measures for comparing the performance of alternative methods for the analysis of water quality variables (pdf, 246 KB)