This paper characterizes the relationship between occupant activities and indoor air particulate levels in a non-smoking office building. Occupant activities were recorded on video. Particulate concentrations were monitored by three optical particle counters (OPCs) in five size ranges at three heights. Particulate mass concentrations were measured gravimetrically and bioaerosol concentrations were determined by impaction methods. Occupant activities and number concentrations were determined with 1-min resolution over a 1-week period.

A study of 132 unoccupied and 60 occupied caravans was conducted to determine levels of formaldehyde and factors which may affect these levels. Repeat monitoring was carried out 6 months later in 50 of the occupied caravans. A questionnaire was also used to assess potential factors associated with the recorded levels. Mean formaldehyde levels of 100 ppb in unoccupied caravans and 29 ppb in occupied caravans were recorded. A negative correlation was found between formaldehyde levels and the age of caravans.

An intervention study was performed in a mechanically ventilated office building in which there were severe indoor climate complaints among the occupants. In one part of the building a new heating and ventilation strategy was implemented by renovating the HVAC system, and a carpet was replaced with a low-emitting vinyl floor material; the other part of the building was kept unchanged, serving as a control. A comprehensive indoor climate investigation was performed before and after the intervention.

Much has been said recently about healthy home environments. For many years anecdotal evidence has been collected about the improved health that residents in R-2000 homes have experienced. CW/Chas been promoting healthy home environment ideas through their Healthy House initiative. But is there scientific evidence behind claims that R-2000 homes are healthier for their occupants?