The Women’s Health Clinic is served by two air handling units (AHUs), AHU 9A & 9B. These existing units are designed to operate in tandem to serve multiple floors in the BJACH, including all floors above the area of work. The existing AHUs are set up to serve dual duct systems, with common cold and hot deck main duct risers. The main duct risers are in a mechanical shaft adjacent to the Women’s Health Clinic. The existing supply, return and exhaust ductwork shall be removed and replaced to meet the new space layout of the 4th floor for the Women’s Health Clinic. The existing constant volume dual-duct (CVDD) boxes will be replaced with
new boxes to meet the required supply air volume for the new space layout. Each new box will be controlled by a direct digital controller. Existing thermostats will be replaced with electronic digital sensors to meet the space temperature setpoint. New air devices i.e. diffusers, registers, grilles, volume dampers, etc. will be provided with the new supply, return and exhaust ducts to distribute the air quantities for the new designed layout. The existing fire/smoke dampers will be removed at the duct penetrations from the mechanical shaft, and replaced with new fire dampers. The new dampers will have adjacent duct access panels for inspection and replacement of fusible links as needed. The existing duct risers will remain in operation throughout the project, and the other areas served by the air handling units.
Per NFPA 90A, there will be smoke detectors installed in the main return ducts prior to entering the main return duct riser in the shaft. Upon sensing smoke in the duct smoke detectors, the AHU will be triggered to be shut down to avoid the recirculation of smoke, as required by NFPA 90A.
The penetrations through the existing horizontal exit between the Women’s Clinic and the Labor and Delivery ward are existing to remain. There are no dampers in these duct penetrations, and per NFPA 101 by reference of NFPA 90A there are no smoke dampers required as the HVAC system is fully ducted. No modifications to the duct penetrations will be made on this project, as that wall and associated penetrations are outside of the scope of work for this project.
Existing medical gas outlets and associated piping (i.e. oxygen, vacuum, air) within the area of the proposed renovations will be removed. The (3) medical gas zone valves in the areas of work will be removed. The removal work of the medical gas piping in the Women’s Clinic will require a shutdown of the medical gas systems. It was found that there are medical gas lines that pass through the project area that appear to be tied in and potentially serve the labor and delivery unit on the south end of the floor. Those lines will remain operational, and will be reconnected to the medical gas risers in the shaft in the Women’s Clinic area.
The existing plumbing fixtures within the area of the proposed renovations will be removed and replaced to meet the new space requirements. All existing plumbing piping i.e. sanitary, vent, domestic cold and hot water, within the project area of the proposed renovations will be removed and replaced. All new plumbing fixtures will be provided with the necessary piping services. New shut-off valves will be installed on each of the domestic cold water and hot water branch piping to serve the area of the proposed renovations.
New sanitary piping located in the electrical room on the 3rd floor will be provided with drain pans to protect existing and new electrical equipment. The drain pans will be an extension of the existing drain pans, and will slope as needed to allow the system to drain to the existing drains. Close coordination with the facility will be required to perform this work, in order to ensure the safety of the construction personnel while working around energized electrical equipment. Existing main storm water riser between the 4th floor ceiling and the floor will be relocated to accommodate the new space layout.