Water stagnation and recommissioning after work or vacancy

Reduce risk from seldom-used branches, water heaters, shower heads and aerosol-producing devices after long shutdowns.

VERT / GREEN

Identify unused outlets and follow utility/manufacturer recommissioning guidance.

JAUNE / YELLOW

Stagnation, biofilm and some temperatures support Legionella growth; renovations can create dead or seldom-used branches.

ROUGE / RED

Complex system, vulnerable occupants, suspect water after long closure or major plumbing alteration: professional recommissioning plan.

Interactive triage

Helps choose the next step; it does not replace design, permits or professional diagnosis.

Outlet unused >2 weeks
Plan careful recommissioning following public-health guidance. Dead leg created by renovation
Correct the design rather than leaving stagnant piping. Unknown water-heater temperature
Verify setting and scald protection without improvising. Regular use and maintenance documented
Keep recommended maintenance/flushing schedule.

Useful tools and data

Branch map
Vacancy log
Water-heater settings

What the professional checks

Find dead legs/stagnation
Check temperatures/scald protection
Set recommissioning plan

Official sources

Checked 2026-08-22.

Santé Canada — Legionella

Related path

Continue with the right tools

These links connect this page to the next useful checks and decisions without repeating the full content.

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