Log Removal / Percent Removal Calculator
Log removal (log credit) and percent removal for single barriers or multi-barrier treatment trains — influent vs. effluent concentrations in any consistent units.
Use consistent units for each barrier (e.g. oocysts/L, PFU/L; NTU only as a rough surrogate).
Formulas
Percent removal = (C_in − C_out) ÷ C_in × 100
Log removal = log₁₀(C_in ÷ C_out) · multi-barrier total = sum of barrier log removals
Non-detect effluent: detection limit is used as C_out (conservative).
Context: SWTR requires 3-log Giardia / 4-log virus removal-inactivation; LT2 assigns 2–5.5 log Crypto treatment by bin — treatment-technique framework, not MCLs.
Percent removal = (C_in − C_out) ÷ C_in × 100
Log removal = log₁₀(C_in ÷ C_out) · multi-barrier total = sum of barrier log removals
Non-detect effluent: detection limit is used as C_out (conservative).
Context: SWTR requires 3-log Giardia / 4-log virus removal-inactivation; LT2 assigns 2–5.5 log Crypto treatment by bin — treatment-technique framework, not MCLs.
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