“ This time it was daylight. There were other people around. Although the hairs were rising once again, he was determined to find a scientific explanation. Why did the blade vibrate in one part of room and not another? Because, as it turned out, infrasound was coming from a fairly new extractor fan. “When we finally switched it off, it was as if a huge weight was lifted,” he says. “It makes me think that one of the applications of this ongoing research could be a link between infrasound and sick-building syndrome.
