BY ROBERT P. MADER of CONTRACTOR’s staff
ITHACA, N.Y. — Tougher Industries, Albany, N.Y., is finishing the mechanical contract for a highly sensitive clean room laboratory, which will be used for nanofabrication teaching and research and development at Cornell University here.
The clean room is part of Duffield Hall, a $50 million state-of-the-art nanotechnology research and teaching facility that will provide updated accommodations for the Cornell NanoScale Science and Technology Facility, the oldest federally supported center in the United States for the building of electronic circuits and devices from single atoms and molecules.
The clean room, which occupies 20,000 sq. ft. of Duffield Hall’s first floor will replace an existing, outdated research laboratory at the university and give students an area for learning nanotechnology processes. In addition to the Class 1000 clean room, the building contains two floors of teaching laboratory space and offices, said Robert Brown, director of construction for Tougher.
Basement and penthouse mechanical rooms that contain 70,000-cfm custom-built air handlers dominate the building.
Tougher has been on the site since the summer of 2001 when site work began. The building sits in the engineering quadrangle at Cornell and is connected with an atrium to the old laboratory space, Phillips Hall.
The rectangular, 150,000-sq.-ft. structure is cast-in-place concrete, covered with a stainless steel and glass exterior. The building has an arched roof with six stainless steel stacks projecting 15 ft. above it.
General contractor for the project was McCarthy Building Cos., St, Louis, in a joint venture with Welliver McGuire.
“The engineer is BR+A [Boston] and they did a great job,” Brown said. “Steve Levin is the principal there.”
Due to the sensitive nature of nanotechnology equipment and the stringent clean environment requirements, McCarthy/Welliver McGuire established Clean Build Protocols throughout the entire clean room construction process. These protocols require strict adherence to special construction procedures to keep the space clean and that protective gear be worn by all those inside the laboratory, including all construction workers.
The general contractor finished work on the footings in December 2001, and Tougher began installing prefabricated piping for the basement mechanical room in the winter of 2002 while the upper floors were still being poured, Brown said. Tougher followed the building upward as each level was completed.
The job required a lot of coordination between trades, Brown said. Tougher performed all the process piping and sheet metal work. Collins & Walton, Elmira, N.Y., installed the code plumbing.
Tougher installed the reverse osmosis deionized water system, lines for gases such as nitrogen, high purity piping and process piping for the laboratories. The firm installed infrared butt fusion welded polypropylene pipe for the clean room and CPVC for the laboratories. USFilter supplied pure water systems.
Both steam and chilled water come into the basement mechanical room from a central plant. Three shell and tube heat exchangers convert steam to hot water and glycol. Two 350-gpm heat exchangers produce about 6.174 million Btuh and a 500-gpm unit produces 4.86 million Btuh. Bell & Gossett pumps move the hot water. A plate and frame heat exchanger and a clean steam generator from Cemline make clean steam for humidification for the clean room makeup air units.
Two large B&G chilled water pumps move chilled water through the building.
The basement also contains laboratory air compressors and a central vacuum system for housekeeping. All the electrical switchgear is down there, as are some of the modular package units from McQuay for comfort cooling in the basement.
The massive custom-built makeup air handler dominates the basement mechanical room.
The 70,000-cfm air handlers in the basement and penthouse, containing two 35,000-cfm fans, were custom built by Custom Air Design. The units measure 18-by-12-by-62 ft. long. They supply makeup air for the clean room.
The basement air handler includes a desiccant dehumidifier from Munters Cargocaire. The air handler feeds directly to the first floor through 120- by-36-in. ducts to 25 Cleanpak International ceiling-mounted re-circulating air handlers. The Cleanpak units each have a capacity of 10,000 cfm.
Reynolds Technology provided the 17 custom-made wet stations and HEPA stations in the clean room.
“They work on the wafers on these benches,” Brown noted.
The workstations are exhausted through a fiberglass-reinforced polyester exhaust duct distribution network and then through a 60-in. diameter FRP duct provided by Primary Plastics. The FRP duct rises from the clean room to the penthouse where the fans are located.
The clean room contains a stainless steel Silane gas exhaust system from Hartzell Fan, which provided the fan for the FRP system as well. Loren Cook Co. supplied the fans for the laboratory exhaust hoods.
The penthouse contains another custom makeup air unit just like the one in basement but without the desiccant dehumidifier. The lab exhaust fans for the second and third floor, and the smoke exhaust fans for the building’s atrium also are in penthouse, along with some modular McQuay units that serve conference rooms and offices.
All those fans exhaust through the roof through six 48-in. stacks, 15 ft. in the air, with round stainless enclosures around them in the same metal as the skin of the building. The enclosures, in some cases, contain items such as steam vents.
Cornell has an existing facility, Knight Lab, from which researchers will move into the new clean room and laboratory space. Knight Lab will then be demolished and the atrium of Duffield Hall will be completed.
“We expect by the end of October that we will be working on Phase Two to finish the building, which is scheduled for a July 2004 completion, but it’s only 5% of the mechanical contract,” Brown said.