The National Centers for Animal Health, a collection of three US Department of Agriculture agencies, is located on 480 acres north of Ames, Iowa; building 9, the newest, is a High Containment Large Animal Housing Facility. Space was added for the approximately 800 employees from two USDA agencies: the Agriculture Research Service (ARS) and the Animal and Plant Health Inspection Service (APHIS). Construction for Building 9 reached $100 million.
Part of a $460 million USDA project, Building 9 is rated a Biosafety Level 3Ag containment structure where disease studies can be done on poultry, hogs and large livestock such as cattle, horses, deer and bison. The building will become central to efforts to learn more about and how to detect cases of mad cow, anthrax and other animal diseases, many of which can be passed to humans.
Building 9, under the guidance of construction manager McCarthy Building Cos., St. Louis, is located within 300 to 400 feet of the other buildings on its own separate acreage. The building contains four levels, including a basement, program floor (where animal testing will take place), a mechanical floor and a mezzanine. It is divided into north and south halves; one half contains training facilities and studies related to an animal brought in with an ailment. The other side is dedicated to agricultural research with healthy animals injected with products to enable the study of effects and treatments.
The building’s 53,314-square-foot first floor—the program floor—houses the containment rooms for large, medium and small animals. Here, scientists and technicians can test for mad cow disease in one room and for anthrax in the next room without the threat of the diseases spreading. The program floor includes four large animal rooms, which are suitable for buffalo, cows, elk or deer, and 14 small animal rooms. A “clean change” shower and “dirty change” rooms allow employees to travel in and out of the rooms without taking any contamination with them.
The basement level contains pumping, waste handling and rendering equipment. The mechanical floor houses mechanical and electrical equipment. The top floor, also known as “the penthouse,” houses HEPA filters for air cleaning that are 99.7 percent efficient. The three separate filters are burned after removal at a high temperature to destroy any infectious diseases that may have escaped.
The total space of the finished building is 156,623 square feet and features 22 totally isolated animal rooms for various species.
Tri-City Electric Co., Davenport, Iowa, brought this most unusual project to fruition electrically. Plans for Building 9 started in 2001. Tri-City provided an estimate—and a subsequent bid—on the project in January 2004, said Paul Lamont, Tri-City estimator. By early spring, the company had won the project. The drawings provided for the estimate and bid encompassed 134 electrical pages. However, they were far from being complete, in part because the project was so unique, Lamont said.
The Tri-City crew went on-site in May 2004 to install components and wiring for the electrical power system as well as lighting, fire alarm, security, lighting control, intercom, paging, data, telephone, decontamination, door control and closed-circuit television (CCTV) systems. Building 9 was erected among existing buildings 1 through 5 with several other buildings to be constructed in the future.
A late start, due to postponed funding by Congress in 2003, and delay in acquisition of specialized sensitive materials, put the fall 2004 construction starting point behind schedule. The Iowa winter was looming and concrete had yet to be poured. The solution was to envelop the entire building under a giant canvas bubble to protect the site from the weather.
McCarthy workers erected a 450-foot-long, 250-foot-wide and 125-foot-high coated polyvinyl chloride bubble on Oct. 22, 2004, to protect the containment concrete, which cannot be poured below 50 degrees. The building’s concrete and conduit work had to be completely crack-free to contain the highly contagious diseases that will be worked on inside the epoxy-coated walls. The bubble not only kept out rain and snow, it was heated to keep the temperature above 50. After the concrete was poured, it was wet cured with dripping water for seven days.
Two 30,000 cfm blowers kept the bubble inflated and provided fresh working air. On average, the electrical bill just to keep the bubble inflated was $1,800 or $2,000 per month, said Joe Squire, on-site project manager, Tri-City Electric.
Tri-City had a large role in the project. The company was required to install galvanized, rigid steel conduit and stainless steel boxes in the containment area. Lighting fixtures and doors in Building 9 are all stainless steel, in fact $1 million worth of it. Engineers deemed stainless steel to best withstand an environment that includes pressurized water washdown, steam and highly corrosive disinfectants during room cleanings.
Disinfectants are not the only hazard. The animals themselves could do significant damage to doors, walls and light fixtures, and all had to be built to withstand the assault. The steel pen doors to the isolated animal rooms can withstand a 1,500-lb. hit at 35 mph.
Fluorescent and other types of lighting fixtures were required to be compatible with the high-tech lighting control and dimming system manufactured by Payne Sparkman, New Albany, Ind. This system provides various lighting programs, including simulating night and day for the animals. Because animals are drawn toward a lighted area, the lighting control and dimming system also allows lights to be turned on or off along a hallway to direct an animal’s movements.
Tri-City Electric also installed wiring and equipment for a CCTV camera and a door control security system. These systems monitor and control access and egress throughout the facility. Controlled access doors allow that only one door (either entry or exit) to any particular containment room can be open at a time, ensuring pressurized rooms stay that way and containment is not breached. Communication Engineering Co. (CEC) provided the security equipment for Tri-City. Finally, the mechanical system provides filtered air both into and out of the building. Decontamination takes place in the animal rooms in which they shut down all air, turn on warming plates and use a combination of chemicals to decontaminate and neutralize the area.
When the building was complete, Tri-City Electric had installed 1,202,574 linear feet—or 227 miles—of electrical wiring.
Of the 11 miles of conduit installed within the concrete pours, seven miles were required to be filled with epoxy. These conduits—embedded in the concrete walls and ceilings—were then pressure-decay tested to ensure they were sealed and would, therefore, prevent any contaminants, bio or otherwise, from leaving any sealed room.
As part of the effort to achieve a tight seal, Tri-City installed solid electrical conductors in lieu of stranded conductors for all wiring within all conduits that were required to be sealed. The use of more commonplace stranded wire was not allowed, since that increased the risk bacterial growth in the strands, which could then contaminate the building, said John Ragsdale, senior project manager.
Brad Anderson, senior project manager, electrical engineer, Merrick & Co., Aurora, Colo. confirmed this. “Conduits, junction boxes, etc., offer leak points,” he said.
Tri-City modified its usual installation method to meet this requirement. “After we pulled wire of any type in the containment areas, we had to completely fill the associated conduit with an epoxy sealant to ensure no contamination could escape any contained area and infiltrate other areas by way of any of the electrical systems,” Squire said. Tri-City was also required to run 100 percent redundant wire in all epoxy-sealed conduit in case any wire failed.
“There is no way contractors would ever be able to replace the wire after sealing off the conduits if there is a problem,” he said.
High containment projects are unique, Anderson said, adding that, “When you superimpose large animals into that environment, it makes it even more unique.” Because of the diversity of needs for the animal containment rooms, changes to original workscope were inevitable. Altogether, there were 1,500 pages of requests for information (RFIs). In addition, about $2 million worth of electrical changes were made.
“This project was more similar to a design/build philosophy than it was to an engineered plan and spec job,” said Doug Palmer, president of Tri-City Electric Co. “That is why we assigned this team of individuals to this project. These individuals ensured the job turned out the way we meant it to be both financially and as a final product.”
“There is nothing like this anywhere else on the world,” said Ranjit Sinha, McCarthy project manager. The security system “is one of the most complicated out there. The complexity is pretty amazing.”
The project was turned over to the USDA in January 2007, and Sinha said there were no compromises.
“The government wanted everything to be just right,” he said.
Anderson also was pleased with the results and the flexibility of Tri-City Electric. “We, as a design team, worked closely with the contractor. Tri-City was good, very creative. They worked well with us. They definitely earn a gold star,” he said.
“Everybody who had a part in it can say they helped build something that has nothing like it on the planet,” Sinha said. EC
SWEDBERG is a freelance writer based in western Washington. She can be reached at firstname.lastname@example.org.