IBM defense: cleanrooms had adequate ventilation, no chemical over-exposure


By Mark DeSorbo

SANTA CLARA, Calif.—William R. Acorn, a Tucson, Ariz.-based HVAC expert, testified in the ongoing cleanroom cancer trial that IBM Corp.'s disk drive plant in San Jose was adequately ventilated, contradicting prior testimony from a plaintiff witness who said the entire facility was negatively pressurized, causing controlled environments to be starved of fresh air.

Acorn, principle of Acorn Consulting Services LLC, told jurors in early February that the cleanrooms in question were adequately exhausted and replenished with fresh air.

"I did an exhaustive forensic analysis of the original documentation of the building, the specifications, and there was a high rate of exhaust for all of the production tools, and that requires a high rate of outside air for the replacement of the exhaust," Acorn tells CleanRooms.

Two former IBM cleanroom workers, Alida Hernandez and James Moore, say IBM kept air ducts closed and failed to remove fumes from chemicals used at the disk drive and printed circuit board plant, where they both worked starting in the late 1960s and early 1970s. Hernandez and Moore allege that exposure to chemicals at IBM later caused their cancers.

An industrial hygienist also testified that air samples taken while Hernandez worked at the computer giant showed she was not over-exposed to toxic chemicals. Clifton Crutchfield, an associate professor of environmental and occupational health at the University of Arizona, told jurors that Hernandez's exposure to chemicals and solvents like acetone, xylene, freon and toluene fell below industry standards.

Crutchfield says he analyzed air samples taken by IBM in 1981 and 1989 from an instrument Hernandez wore while working at the Cottle Road (San Jose) facility. Hernandez and other employees wore the devices as part of an IBM monitoring program. He also said air samples from the disk-coating operation where Hernandez worked showed chemical exposure well below the threshold set by the American Conference of Governmental Industrial Hygienists.

"It's a well-controlled operation," says Crutchfield, who has done consulting work for IBM and the semiconductor industry, the Mercury News of San Jose reported.

Chris Andrews, an IBM spokesman, says the company lawyers will continue to demonstrate there was no fraud on Big Blue's part. "We did not withhold harmful effects in the work environment," Andrews told CleanRooms. "We believe our company is a model for worker safety. We have always operated to the highest standard to employment health and safety. We went beyond industry practice and mandates and have made employee safety the highest priority."

But out of 38 people who responded to a Quick Vote question on, 24—or 63 percent—believed IBM should be held responsible for not protecting cleanroom workers against cancer risks, while 37 percent—or 14 voters—think IBM is just another victim of a litigious society.

Acorn, who has helped build more than 100 cleanrooms for numerous chip and microelectronics manufacturers, including IBM, Motorola Inc. and Intel Corp, would not comment on the numerous cancer cases among IBM employees past and present.

He laughed, however, when asked about statements made by plaintiff witnesses, specifically, statements regarding dampers on air intakes being closed.

"They have no way of verifying that statement," Acorn says. "You can't have an absence of outside air in a building that uses a lot of process exhaust. It's impossible."

"Erroneous" is how Acorn, a speaker at CleanRooms West 1999 in San Jose, described the testimony of plaintiff witness Robert Morris, president of airflow and control systems manufacturer FlowSafe Inc. (Denville, N.J.). Morris, along with computational fluid dynamics expert Scott Reynolds, an engineer at Binghamton, N.Y.-based Computer Aided Engineering Solutions, created virtual reality models of cleanrooms to simulate airflow and working conditions. Testimony on computational fluid dynamics models, however, was tabled in a deal between lawyers from both sides.

"Claims were made that the analysis by the plaintiffs was done giving IBM the benefit of the doubt and using best practices of the industry, and in fact, they used the worst practices, and not use recommended practices," say Acorn, who cited the Industrial Ventilation Manual, published by American Conference of Governmental and Industrial Hygienist, throughout his testimony.

He also refuted plaintiff expert claims that placing exhausts at the far end of cleanrooms was the best practice for ventilating rooms with chemical processes through an adjacent space. "It doesn't even pass the common sense test," Acorn adds. "It's like exhausting a bathroom through your living room."

He also testified that IBM provided "good exhaust capture" at such production tools as spin coaters, adding that plaintiff witnesses made significant errors in calculating the effectiveness of cleanroom filtration.

"One of the plaintiffs experts says that it was capturing only 50 percent of the chemical vapors, and this was based on the rationale that it his view that it was likely to be zero percent as it was 100 percent—and so he chose 50 percent," Acorn says. "It's not rational at all. That's like saying every time you start your car, it will only start 50 percent of the time."

He added that exhaust capture is greater than 90 percent, based on practical experience, and the design and construction practices of the facility were "in keeping with the industry...worldwide cleanroom standards."