Sewage is Category 3 — the standard says remove, not clean
The industry water-damage standard, IICRC S500, classifies sewage as Category 3: grossly contaminated water. Under that standard, porous materials it soaks — carpet and pad, drywall, insulation, particle-board flooring — are typically removed and discarded rather than sanitized in place. That is why a sewage job is scoped so differently from a burst-pipe job.
Source:IICRC — Institute of Inspection, Cleaning and Restoration Certification