Proposed revision to NSF/ANSI 53: Drinking Water Treatment Units – Health Effects (53i132r2).
The proposed revision clarifies the test requirements for point-of-use (POU) versus point-of-entry (POE) devices in each relevant subsection of Sections 6 and 7 of NSF/ANSI 53. An informational annex is also being added with examples of how to scale up units with granular media of all kinds and units with carbon blocks.
Revision 2 addresses comments received during the r1 adjudication ballot (12/14/21) and 1) clarifies that POE systems are exempt from flow-control requirements, 2) adds backwashing to the full-scale and scale-up test procedures for POE systems where the full-size unit needs backwashing, 3) allows using one full size POE unit or two properly sized scaled down units, and 4) expands flow rate calculations and guidance in Informative Annex 7. |
