Fitting ultraviolet germicidal devices (UVGI) into office ventilation systems:

• killed 99% germs on surfaces within the ventilation system
• reduced sick building syndrome by 20% overall
• reduced work-related respiratory problems by 40% overall (by 60% in never-smokers)
• reduced work-related mucous-based problems by 30% overall (by 40% in people who suffered from the atopic illnesses asthma, hay fever or eczema)

The study by Dick Menzies and colleagues from Montreal Chest Institute's Respiratory Epidemiology and Clinical Research Unit (Canada) covered 771 office workers in Montreal. UVGI was turned on for twelve weeks, then off for four weeks, back on for twelve, off again for four, etc. for 48 weeks.

Applied to most US offices, the findings indicate a possible benefit for four million workers. Installation costs would be more than outweighed by savings in days off work.

See also Sick building syndrome