UNI EN 12255-15 : 2004

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and abbreviations
5 Principle and procedures
6 Aeration tanks, test-water, equipment and chemicals
  6.1 Aeration tanks and aeration installations
  6.2 Measuring Equipment
      6.2.1 Dissolved oxygen probes (DO probes)
      6.2.2 Recording of the dissolved oxygen concentration
      6.2.3 Temperature measurement
  6.3 Chemicals
      6.3.1 Sodium sulphite
      6.3.2 Cobalt catalyst
      6.3.3 Nitrogen and pure oxygen gas
  6.4 Test-water
7 Procedure
  7.1 Planning of testing
  7.2 Advance preparation and responsibilities
  7.3 Filling of the tank with test-water
  7.4 Installation of the DO probes
  7.5 Addition of chemicals
      7.5.1 Cobalt catalyst
      7.5.2 Sodium sulphite
  7.6 Gas injection
  7.7 Data collection during a test
  7.8 Data analysis
8 Precision and accuracy of results
  8.1 Standard oxygen transfer rate
  8.2 Standard aeration efficiency
  8.3 Specific standard oxygen transfer efficiency
9 Presentation and interpretation of the results
Annex A (normative) Alternative test and evaluation
        procedure
  A.1 Principle
  A.2 Measurement of the oxygen saturation value
  A.3 In-situ calibration of the DO probes
  A.4 Determination of the oxygen transfer coefficient
Bibliography

Covers the non-steady state measurement of the oxygen transfer rate and the oxygen transfer efficiency of aeration systems in activated sludge aeration tanks (see EN 12255-6) when filled with clean water.