At Class A, disinfection stops being a process you run and becomes a program you're accountable for — one governed by a specific federal regulatory framework, quantified with CT tables you must actually apply correctly, and constrained by a compliance requirement (disinfection profiling) that exists specifically to stop utilities from cutting corners on microbial protection while chasing disinfection byproduct reductions. This is the first of two Class A guides on this topic; Part II covers DBP compliance and alternative disinfectants in depth.
The Surface Water Treatment Rule Framework
Because pathogens like Giardia and Cryptosporidium can't be measured reliably or quickly enough at the tap to serve as a real-time safety check, EPA regulates disinfection through treatment technique (TT) requirements rather than a simple maximum contaminant level. A treatment technique requi