Sensitizations to fungi that can be isolated when the fungi are removed from air conditioners are often shown by people suffering from various symptoms while in air conditioned rooms. It was shown that by using specific challenge tests fungal spores in air conditioners can give rise to allergic symptoms. The specific therapy prescribed for these reactions was hyposensitization. After this therapy, more that 70% of the patients could live and work again in air conditioned rooms without developing symptoms.

In the study a collection was made of bacterial and fungal spore samples from twelve office building ventilation systems. Measurements were performed with and without humidification. In none of the cases were ventilation or humidification systems found to act as bioaerosol sources. There was no observed difference between bioaerosol counts in offices with and without humidification. In all ventilation systems the microbial levels decreased.

An examination was conducted of thirty single family homes with either high or low house-dust mite allergen levels in mattress dust, with regard to ventilation, thermal climate, and air quality. High concentrations were associated with the difference in absolute humidity between indoor and outdoor air, also with low air change rates, especially in the bedroom. The research found no correlation between concentrations of TVOC or formaldehyde in bedroom air and HDM allergen concentration.

Describes and investigation of house-dust mites in 96 Danish homes with one or more members with asthma. All the homes were measured for air exchange rates, humidity and temperature. The study found a positive correlation between indoor air humidity and mite concentration and an inverse correlation between house-dust mite concentration and indoor air exchange. House-dust mite concentration was higher in the houses with mite-allergic persons. In 76% of the homes the concentration was above the proposed limit of 10 mites/0.1 g dust. This was so in 48% of the non-allergic homes.

An experiment was performed in a lecture hall on students, to assess the effect of ventilation noise on concentration and fatigue. The students were tested with the ventilation fans both on and off. As a group the students reported more fatigue during lectures when the fans were operating. States that this environmental effect explains about 39% of the variance in fatigue ratings and may be sufficient to affect adversely the attention of students within these settings.

The effectiveness of individual commercially available portable indoor air cleaning units were tested for their removal of dust particulates, tobacco smoke particulates and vapour phase constituents, viable and total fungal spores, pollen, and gaseous contaminants, and formaldehyde. A clean air test chamber was used. The results presented represent initial use. It was found that HEPA and electrostatic precipitator system demonstrated the highest efficiency in relation to particulate contaminants, with electret filter systems close behind. Least effective were ionizers and ozone generators.

Assesses sick building syndrome symptoms and perceived odours for daycare workers, in relation to ventilation rates in Finnish daycare centres. Thirty centres were chosen for the study, which consisted of 268 female nursing workers. The workers completed a questionnaire. Mechanical supply and exhaust ventilation systems constituted most of the centres' systems with 37% having mechanical exhaust alone. The authors noted a very varied exhaust air flow in the children's rooms, from 0 to 11 L/s per person. Air change rate varied from 0 to 5 m3/hm3.

The intensity and acceptability of body odour was assessed 29 times on entering an experimental auditorium occupied by 106 women, by 40 female and 39 male judges. The experiment lasted 3 hours 50 minutes and the ventilation rate was varied while the air temperature was maintained at around 20-21 deg C. CO2 was measured throughout. It was found that there were no substantial differences in the ventilation rates required in rooms occupied by men and women. In order to satisfy 80% of people entering a space, a steady-state ventilation rate of about 8 L/sec person is necessary.

Cat and dog allergens in settled dust and airborne cat allergen were studied in day-care centres, with links explored between pet ownership among children and staff, ventilation and cleaning. The special centres were allergen-avoidance day care units. Control was performed by 22 conventional day care centres. Allergen levels were measured using ELISA and personal air samplers, and air change rate per hour was noted. A questionnaire was distributed for the other data. No cats or dogs were kept by children at the allergen avoidance centres in contrast to the control.

The study evaluated the strength of tobacco smoke odour by sense of smell. Similar tests were done for other irritants in tobacco smoke. Concludes that an outside air supply of 35 to 40 cfm per smoker is required to remove objectionable odours of fresh cigarette smoke. Also concludes that there in no way to ascertain whether the ventilation requirements for controlling smoke, odour and irritation effects are adequate to protect a non-smoker from possible effects of nicotine and other poisonous elements of smoke of unknown toxicological thresholds.