2.5. Ozone generation
Ozone was generated photochemically with a thermostated mercury
lamp housing controlled by a high performance variable power supply
using air (medical grade) as described previously (Clausen et al.,
2001). The ozone generator was adjusted manually to maintain a 50
± 5 ppb ozone concentration inside the chamber for at least 1 h before
the start of the application of KCA or turning on PIAF. The ozone–air
mixturewith a flowrate of about 0.5 l/minwas fed through a ¼” Teflon
tube into the chamber via the air inlet of the climate chamber. Ozone
was measured with a calibrated API 400 UV ozone monitor (Teledyne
API, San Diego, CA).