Variance re-opening request for building studies, 30 [name], Nov 2005

NYC 9/11 Public Portal Document

Mr. Chris Alonge - NYS DOL Variance Re-Opening Request - File 05-0919 Airtek Project #05-0867 - November 17, 2005

4. Check that emergency egress paths are clear of debris and that emergency egress doors are operable. 5. Cover over holes in concrete deck with cleats to eliminate fall hazards. 6. Make sure exit signs clearly indicate emergency egress paths. 7. Remove sharp welded wire mesh points from slab edges. 8. Remove loose overhead debris. 9. Padlock doors at temporary plywood barrier partitions at south end.

Elevator Operation:In order to properly plan for abatement and demolition sequencing, operational capability of the building elevator systems must be tested, and the elevators must be operated.

1. Vent elevators to eliminate piston effect impact to building exterior. Through-wall relief vents will be cut in elevator shaft walls for low-rise, high-rise and service elevators. Wire mesh will be place over the opening to protect the shaftway. 2. HEPA vacuum "Gross" clean, service and test all machine room, hoistway and pit equipment. All cleaning (HEPA-Vacuuming/ Wet-wiping) will be conducted by a NYS DOL Certified Asbestos Contractor. 3. Perform troubleshooting of the microprocessor and solid state motor drive systems for safe and proper operation. 4. Perform full load inspection and testing of each selected elevator. 5. Perform acceptance inspection and testing as required by NYC code for temporary construction use of elevators. 6. File with the New York City Department of Buildings to reclassify the selected elevators for construction use to secure temporary use permits. The elevators that are not going to be used during the construction phase shall be filed for decommissioning.

As described below and on the attached drawings, the piston effect of the elevators and their potential to expel interior air into the outside environment will be addressed through the installation of engineering controls, and the application of monitoring specific to this operation.

Engineering Controls: Elevator banks in the building currently vent pistoned air to the elevator machine rooms and then to the outside air through louvers. The forcing of air to the exterior of the building will be prevented by: 1) the installation of critical barriers (two layers 6-mil poly and plywood, caulked at the edges); 2) the opening of alternate vents at the top of the shafts to allow air to vent onto the top floor of the building, and 3); the reduction of elevator velocity to reduce the piston effect.

Monitoring: Air monitoring for asbestos (TEM) will be conducted on a daily basis at the exterior of the critical barriers for each elevator at the

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