Portable ozone monitor fitted with low concentration-range detection head. Operating range 0~0.5ppm ozone with display in ppm or mg/m3. Gas sensitive semiconductor [GSS] sensor for accurate low-level measurements, T90 response approximately 100s. Operation from mains power supply or battery pack (4h operation). Internal data logging for 8000 points with software and cable for download to PC, or data logging direct to PC. Application for indoor air quality measurements.