NYC 9/11 Public Portal Document
Page2
Milford Management
10/17/01
CLEANING PROCEDURES FOR VERTICAL HVAC AND EXHAUST
DUCTING
Step 1. Perform a thorough visual inspection to determine the accessibility to the
system. Vertical shafts often pose many challenges for cleaning procedures
and remote inspection devices may be used.
Step 2. A remote vacuum/collector device will be attached to the duct to collect the
contaminants once they become dislodged inside the ducts.
Step 3. The vacuum/collector is connected to the lower most portion of the shaft
allowing the forces of gravity to help pull the debris into the vacuum system.
Step 4. Additional access to the vertical shaft will be gained on each floor of the
building by inserting the cleaning tools into the duct and working the debris
toward the shaft and then down to the point of vacuum hook up.
Step 5. At the time of the cleaning of a particular floor's duct work, it is imperative
that the outlet and register openings of all other floors in the line be sealed
off to prevent contamination from coming out of the system. Moreover, this
helps in maintaining the negative air pressure within the system and improves
the dust collection capability of our vacuum system. We will work with your
staff in order to schedule accessibility to all units within a line in order that
we service at least one line per day.
Step 6. Each grill or register is manually cleaned and degreased prior to reinstallation.
Any damage or conditions that affect the proper functioning of the system will
Be reported to the building representative and management.
NYC-WTC 000120682
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