The influence of air ions, temperature and humidity on subjective wellbeing and comfort

The study assesses the effects of ambient temperature, humidity and air ionization in an office environment on the rating of thermal comfort, stuffiness, alertness, well-being and other subjective responses. The incidence of headache, nausea and dizziness was also recorded. A total of 106 male and female subjects made daily records of their assessment of the environment and their health over a 12-week period. Temperatures above 23°C were associated with increased sensations of stuffiness, discomfort and unpleasantness, but appeared to produce a decrease in the number of complaints of headaches.The office environment was found to be depleted in small air ions. The introduction, on a double-blind basis, of a negative ion generator increased the subjective rating of alertness, atmospheric freshness and environmental and personal warmth. Ions reduced the complaint rate for headache by 50% and also significantly reduced the number of complaints of nausea and dizziness. Night-shift working was associated with a very high complaint rate of both subjective discomfort and ill-health. Air ions appeared to be particularly effective in reducing these problems at night.