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PROCEDURES FOR CLEANING, SANITIZING, and COATING OF
AIR HANDLING UNITS and ASSOCIATED DUCT WOR

All personnel shall wear during this process certified respirators, safety glasses and protective clothing according to OSHA standards 29-CFR-1910.134, 29-CFR-1919 and 20-CFR-1910.20.

 CLEANING
Cleaning procedures shall be accomplished by the utilization of specialized equipment as required (i.e. high suction vacuums utilizing HEPA filters, high pressure washer, air compressors, Nikro duct brush system, etc.).  All mold, mildew, lint, hair, fungi, dirt and other foreign materials and residues shall be removed from unit using Source Removal.  Source Removal is the mechanical cleaning of system components to remove all contaminates not conducive to an Air Handling Unit (AHU) and associated ductwork.  During the cleaning process any area being cleaned shall maintain a negative pressure to prevent cross contamination of other areas.  Shut off all electrical power to AHU and heat strips.  Install lock out/tag out device to disconnects and breakers.  All electrical components and items within the AHU that are sensitive to, or could be damaged by the cleaning process, shall be properly protected while work is being performed.  All fire alarm and smoke detectors are to be removed by a qualified technician before work begins and reinstalled after work is completed.

Cleaning begins at the return air plenum and continues following direction of air flow until AHU is completed.  When vacuuming interior liner, take special care not to damage liner.  Any liner that needs replacing before cleaning begins will be photographed, and owner shall be informed of condition of liner before proceeding.

Using HEPA filtered vacuum, clean return air plenum and filter compartment (discard old disposable filters, clean washable filters) do not install new filters until completed or unit is turned on.

Clean coils using a non-toxic, non-acid based coil cleaner (BBJ Micro-Clean).  Coils shall be thoroughly cleaned on both supply and return surfaces so air flow and heat transfer is not inhibited.  Back to back coils must be removed for proper cleaning of each coil.  Coils shall be thoroughly rinsed, using high pressure sprayer, with clean water to remove all residues.  Care shall be taken to prevent damage to coil.

Vacuum blower compartment insulation liner and sealed if required.

SANITIZING
Sanitizing of AHU interior shall be accomplished by the utilization of pump sprayer and Oxine Sanitizer, mixed and applied according to manufacturer’s instructions.  Thoroughly wet all non-porous material in AHU, taking special care to prevent over spray to any porous material.

COATING
1.      Spray fumes shall be controlled by Negative Air Equipment during and two (2) hours after application, exhausting volatiles to the outside.

2.   Coils, blower wheels, vanes, electrical equipment, sensing and control devices shall be covered.

3.   Anti-microbial coating (Fosters 40-20) shall be applied with airless painter according to manufacturer’s instructions.  Coating shall be sprayed directly onto interior surfaces.  A continuous film must be achieved by the coating application.  Thickness of coating will be determined at time of application.

4.   Equipment must remain off twelve (12) hours following application to allow for proper curing of coating. 

5.   Maximum outside air must be brought in through the system for at least forty-eight (48) hours after application of coating.

6.    Clean-up work area.

PRE-STARTUP
1.      Remove all protective coverings from equipment.

2.      Install clean return air filters.  Check for bypass around filters and correct if needed.

3.      Install drain pan chemical treatment.

4.      Have qualified technician install fire alarms and smoke detectors.

5.      Remove lock out/tag out device and turn power on.