Bring these

• Wet-floor signs and barrier kit
• Flashlight
• Splash goggles
• Waterproof chemical-resistant gloves

1. 1Stop fixture usePost the restroom out of service and notify nearby occupants. Stop connected appliance discharge when staff can safely do so through normal controls.
2. 2Map the patternRecord which fixtures back up and which floors are involved. If a lower drain rises when an upper fixture is used, report that existing observation rather than deliberately recreating the overflow.
3. 3Check the service historyTell the plumber about prior backups, recent renovations and any drain chemicals already used. A shared stack or main requires a different response from one dirty sink strainer.
4. 4Arrange the right helpRequest a plumber or drain contractor equipped to diagnose the affected line. Building staff should not improvise with a small hand snake on a shared commercial sewer blockage.
5. 5Reopen deliberatelyAfter drainage is restored, have contaminated areas cleaned by trained staff with appropriate protection. Reopen only when the cause, cleanup and safe fixture operation have been checked.

Record the exact location, observed condition, time, actions taken, person contacted and follow-up owner. Keep unresolved items visible. A completed checklist means the check was performed; it does not automatically mean the equipment passed or is safe.

CDC: protecting workers handling human waste — https://www.cdc.gov/global-water-sanitation-hygiene/about/workers_handlingwaste.html Use the installed equipment manual and your site plan for equipment-specific procedures.