Indoor air quality (IAQ) challenges outnumber all others in the health care industry. Unfortunately, the cost conscious powers that be have failed to make the management of critical infection control systems a top priority.
Concentrations of 54 volatile organic compounds (VOCs) and ventilation rates were measured in four new manufactured houses over 2-9.5 months following installation and in seven new site-built houses 1-2 months after completion. The houses were in four projects located in hot-humid and mixed-humid climates. They were finished and operational, but unoccupied. Ventilation rates ranged from 0.14-0.78 h-1. Several of the sitebuilt houses had ventilation rates below the ASHRAE recommended value.
We studied the effect of ventilation and air filtration systems on indoor air quality in a children's day-care center in Finland. Ambient air nitrogen oxides (NO, N02) and particles (TSP, PM10) were simultaneously measured outdoors and indoors with automatic nitrogen oxide analyzers and dust monitoring. Without filtration nitrogen oxides and particulate matter generated by nearby motor traffic penetrated readily indoors. With chemical filtration 50-70% of nitrogen oxides could be removed. Mechanical ventilation and filtration also reduced indoor particle levels.
ASHRAE Standard 55-1992, Thermal Environmental Conditions for Human Occupancy, is mainly a prescriptive standard intended for occupants with primarily sedentary activity. This article discusses some of the issues being addressed during the proposed revision. The proposed revision will include an analytical method based on the PMVPPD method, where different levels of comfort may be specified. Using the analytical method requires better dialog between the client (builder, owner) and the designer.