Laboratory Accreditation Section Identifier

Laboratory Accreditation

Dissolved Oxygen Proficiency Testing

Dissolved Oxygen Proficiency Tests are now available from three Proficiency Test (PT) providers: RTC, Phenova, and Advanced Analytical Solutions, Inc. This meets the “readily available” threshold in WAC 173-50-070, so Dissolved Oxygen PTs are required when Dissolved Oxygen (DO) is listed on the lab’s scope. This requirement came into effect on July 1, 2014. Since labs have one year to complete their first two DO PTs, labs renewing after June 30, 2015 need to have two DO PTs submitted with their renewal application.

As with other parameters, if a lab passes both DO PTs in their first year, then only one PT is required in the following and subsequent years for as long as they continue to pass the tests.

Note that labs accredited for biochemical oxygen demand (BOD) are not necessarily accredited for DO; in that case they will not need to do PTs for DO.

Proficiency testing sample providers lists all current providers of proficiency tests.