Preserve the useful detail
Check the live instructions, note affected fixtures and neighbors, use only the directed cold outlet, record time, and report through the current path if unresolved.
The decision on display
Do not transfer the hazard
Do not improvise a hot-water flush, drink unexplained changed water, or treat one color as a diagnosis.
Make the proposed work comparable
Separate utility response, premise inspection, heater service, fixture cleaning, sampling, treatment, and post-work verification.
CURRENT PRIMARY SOURCE