“Hospital construction and reconstruction is unique,” says Steve Pacini, a project manager at San Francisco-based Herrero Construction Co. “There are so many variables that things can get crazy.”

Even though he’s Herrero’s go-to guy for managing projects that others don’t want to touch — ORs, ICUs, asbestos removal — Pacini, a 27-year veteran of hospital construction, doesn’t use words like “crazy” casually. But in this case he’s referring to a recent construction job he oversaw at the University of California San Francisco, a teaching hospital that ranks among the top 10 U.S. medical centers.

The project, which exploded in complexity, originally started as a small refurbishing job at UCSF’s cardiac department. But that changed when the university decided to install a Stereotaxis unit, a machine that uses two powerful 4-ton magnets to pull a catheter through a heart patient’s circulatory system. Because the machine, which is remotely controlled, can pull the catheter perfectly through the center of a vein or artery, avoiding scrapes with plaque or walls, it considerably lessens the procedure’s risk and length.

For UCSF, installing the Stereotaxis would be a coup: It would be the first unit of its kind on the West Coast, adding an ultra-sophisticated new tool to a cardiac unit already acknowledged as one of the nation’s best.

But there was a rub. The Stereotaxis magnets were so powerful that they would have to be completely shielded. With MRI machines located only two floors below, it was crucial that no magnetic fields whatsoever leak out and cause distortions. Pacini would have to oversee the construction of a room within a room, cloaking a 600-square-foot space in layers of siliconized steel. It was a type of construction that nobody on the West Coast had ever undertaken.

There was a second rub – one that turned an already complex project into a seemingly impossible one. The space that would accommodate the Stereotaxis unit is wedged between the pediatrics ward above and the hospital’s heart, kidney and vein transplant ORs below. UCSF made it clear that there could be no noise during construction, even though Pacini’s crew would have to tear out one side of the building’s fifth floor to begin work.

“We had to invent and develop a slew of anti-noise methods,” says Pacini, “including quiet drills, and anything and everything to lessen or eliminate the sounds made by dropping studs, hammering, shooting staples and all the other noises construction creates.”

Pacini’s crew came through. Susan Grizzle, RN, who manages the Stereotaxis and other diagnostic equipment on the fifth floor, says that there were only three occasions over the life of the project when she received minor complaints about noise from the construction. “I personally never heard a sound. I still don’t know how they did it.”

What was originally estimated to be a four-month project eventually stretched out to almost a year. Because Herrero had to invent building methods as it went along, the company insisted that UCSF make the project timeline open-ended. Aware that Herrero had 30 years of experience in hospital construction, much of it on the UCSF campus, the university agreed.

“Every day was a learning curve,” says Pacini. “The room was so small there was no place for storage, so we had to move materials back and forth constantly.” There was also the health threat posed by siliconized steel dust, which required crew members to wear respirators and eye protection in an often stiflingly hot space. “We soon got a rhythm. Still, some people quit and we wound up with basically a Herrero crew. Because we’d all worked together before, we were able to weather the challenges pretty well.”

The focus of the crew’s efforts were 4-foot-x-8-foot sheets of siliconized steel sheeting, each .032 inches thick. “They were razor sharp, but fortunately we suffered only two cuts on the job,” says Pacini. The workers installed a total of 12 layers of the sheeting to create a 3/8-inch shield around the space where the Stereotaxis would eventually sit. They laid four layers at a time, criss-cross. Since each square foot of the material weighed 32 pounds, the men had to use jacks to help them lift the sheets into place.

“First we built a firewall, then a secondary wall, to which sheets were attached. Where sheets joined, the gaps could be no greater than 2 millimeters. It was easy to build the walls, but when we got to the ceiling, it needed reinforcement.”

Pacini says the work was tedious and painstaking, “especially lining up drill holes for ceiling and floor anchors — we had to use laser templates to do this. Also, we had to run conduits in a tight crawl space between the top of the installation and the sixth floor. We surrendered many weekends to get this done. We had started working regular eight-hour days, five days a week, then quickly ramped up to nine hours a day, six days a week.”

When the job was complete, the crew received a letter from a Stereotaxis executive who commented that his company had never seen such a perfect installation. “It was a great morale booster. We were spent; we’d been on the job for over a year.”

Today, all of his crew’s shielding work lies hidden behind a nondescript light beige wall, colored the same as all the rooms and corridors on the rest of the floor. Unless somebody tells you otherwise, you don’t know it’s there.