scope:

The methods described under these standard guidelines provide several proven techniques for measuring oxygen transfer under process conditions. Nonsteady state, offgas, and inert gas tracer methods are described in the body of this manual, which is followed by a brief discussion of comparisons among methods. The methods presented are considered to be well developed and provide satisfactory precision for a wide range of aeration processes in suspended growth biological systems. Because a wide range of process variables and wastewater characteristics which impact the precision (and accuracy) of these methods are difficult to control, the methods are offered as standard guidelines and are not recommended for compliance testing of aeration equipment.