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NYC 9/11 Public Portal Document

diameter. The study tested cleaning using vacuums with and without HEPA filtration.

An Air Filtration Device (AFD) is a local exhaust system with HEPA filtration that is capable of creating and maintaining a negative pressure differential between the outside and the inside of the work area. The AFD functions as a stand-alone piece of equipment in a room. During the study, the AFD was used as an air-polishing device, to capture dust particles that became airborne as a result of disturbances caused by the cleaning activities. The study tested cleaning with and without use of AFDs.

Shop vacuums are easy to maneuver and are designed to pick up dust, shavings and debris. Upright vacuums are designed for use on horizontal surfaces such as floors. For purposes of the study:

The Eureka® and Hoover® upright vacuums were purchased both as devices with HEPA filtration and as devices with standard bag filtration. The Ridgid® and Craftsman® shop vacuums were interchangeable. (Both can be changed from a standard cartridge filter to a HEPA-rated cartridge.)

Wet vacuums are designed to clean horizontal porous surfaces with soap and water (shampoo). The wet vacuum used in the study was an upright model, providing a suction head lift of 103 inches of water. Suction head is the measure of the suction capacity of a wet vacuum pump. In this case the wet vacuum pump is capable of lifting water 103 inches.

Table 3.0 identifies equipment manufacturer and model used in the study. However, there was no intent of the study to compare manufacturers or the relationships between any particular devices. The objective of the cleanup was to confirm the effectiveness of cleaning of individual spaces using different equipment.

Equipment Manufacturer and Model Make Model Nilfisk^ CFM127 Hoover® (HEPA) U6459-900

252:^:: U5O46-93O ■I Craftsman® 113.170250 Eureka" (HEPA) Eureka® 7618 Ridgid® WD17351 Carpet Express® ACSI®(AFD) 400/600 ForceAir 2,000® EC (AFD) ■i /1000/2000 14

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