for off-road diesel-powered machinery use.

Mary Nichols, chairwoman of the California Air Resources Board, offered no explanation when The Chronicle questioned her about the diesel emissions miscalculation. She was recently asked why the air board estimate of a nitrous oxide source was off by at least a factor of two - air board scientists have since revised their numbers, and data show the estimate was off by 340 percent. Nichols' response: "I can't answer that for you."

Nichols was emphatic, though, when asked whether she has concerns about other scientific calculations made by air board scientists.

"No, no, no, no, no, no, no and no," she said.
http://www.sfgate.com/cgi-bin/articl...#ixzz11iqEfuN9