Exhaust system cleaning procedures and access agreements, Jan 2003

NYC 9/11 Public Portal Document

DRAFT Exhaust System Cleaning Procedures

1. Identify the system to be cleaned including exhaust fan (mushroom), number and location of risers, and apartments or common spaces affected.

2. Determine how many floors on a riser will be cleaned as part of one continuous cleaning (5-10 floors).

3. Lock out and tag out the exhaust fan.

4. Attach a local capture, HEPA filtered. Air Filtration Device (AFD) to the lowest opening of the riser to place the system under negative pressure (exhaust vent in an apartment at bottom of riser being cleaned).

5. Insert and inflate isolation/zone pillows, as necessary to isolate system, so that floors beyond the cleaning scope area outside the work zone.

6. Remove the mushroom assembly from the roof mounting.

7. Disassemble and clean the mushroom assembly using HEPA vacuums with brush attachments and wet methods, as necessary to remove dust (any electrical equipment will not be cleaned with wet methods).

8. Remove and clean all bathroom and kitchen exhaust grills inside affected apartments.

9. Clean all branch ducts from inside the apartment bathrooms and kitchens, using HEPA vacuums with brush attachments and wet methods.

10. Reinstall exhaust grills and install one layer of 6 mil poly over grills and secure in place with painters tape.

11. Clean the main riser from the roof or top most floor of the cleaning zone, using a combination of techniques including whips, brushes, and compressed air.

12. Reinstall the mushroom once the riser or top zone is cleaned.

13. Remove the poly barriers, covering the exhaust grills, while the riser is still under negative pressure so that any loose dust or debris will be sucked down to the capture system.

14. Disengage the local capture system and relocate to another section of the riser or to another riser.

15. All work will be accomplished by a DEP certified Asbestos Handlers.

16. All work will be supervised by a DEP certified Asbestos Handler Supervisor.

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