This paper describes radon diagnostics and mitigation in a school the U.S. Environmental Protection Agency (EPA) classified "difficult to mitigate." The school had subslab utility tunnels that served as the outside air and return air mixing chamber for the heating and ventilation system. The heating and ventilation system depressurized the tunnel, sucked radon from the soil, and distributed it to school rooms. Extensive diagnostics were conducted to test mitigation options and to provide mitigation design parameters.

This study examines the use of energy recovery ventilators (ERV) in two schools located in a Southwestern arid climate as an energy-efficient means of providing acceptable ventilation to the classrooms and the corresponding effect on indoor air quality (IAQ) contaminant indicators. The effect of cleaning the existing systems· on thermal comfort conditions were also examined. IAQ measurements were made in selected classrooms with respect to carbon dioxide, viable and non-viable bioaerosols, volatile organic compounds, and respirable particles.

Mechanical ventilation systems, designed to meet ASHRAE's Standard 62-1989 and to modify building pressures, were installed in two New Mexico elementary schools to reduce elevated levels of indoor radon, carbon dioxide, and airborne particles. Although the systems did not meet design conditions for outdoor air delivery, ventilation rates were increased by factors of 2 to 4 over pre-existing natural ventilation rates, and levels of indoor air pollutants were significantly reduced.

National Institute for Occupational Safety and Health (NIOSH) Health Hazard Evaluation Reports (lllIER) involving schools provide a perspective on the building-related factors associated with indoor air quality complaints. Generally, the school lffiERs reflected multiple building factors associated with the complaints.

A research program was undertaken by the National Institutes of Health (NIH) to investigate ventilation performance of different laboratory configurations and their effect on the laboratory hood. The intention is to provide a basis for guidelines aimed at maximizing laboratory hood containment.

In March of 1996, a new Elementary School was occupied which is the first in the United States to utilize the concept of displacement ventilation as the primary means of providing both good indoor air quality and thermal comfort. In addition, the integrated "sustainable" design concepts of the facility also address other important factors including: siting, programming, lighting, acoustics, energy efficiency, classroom computer usage, and access for planned HV AC preventive maintenance.

The purpose of the study was to assess actual ventilation, indoor air quality and also the quality of repairing process in the Finnish schools. The measurements that included ventilation rate, co2 and particle concentrations, and temperature and humidity in the classrooms were carried out in 20 schools. Repairing of schools were studied on the basis of 32 schools. The typical needs for repairing HY AC-systems and building structures and also typical repairing measures and faults were reported. The most common problem was the classrooms' old-fashioned or even missing ventilation devices.

In a university building in Boston, IAQ complaints prompted an increase in outdoor air ventilation, causing a large increase in energy use. C02 readings were then taken in an auditorium, cafeteria, offices, and classrooms. The readings were used to calculate occupancy estimates and to simulate operation of a demand-controlled ventilation (DCV) system. The differential equations were solved in a spreadsheet program using a Runge-Kutta macro. A PID control system was also simulated. Ventilation adjustments were input to DOE-2 to estimate energy savings. A two year payback was estimated.

The results from the Norwegian project "Indoor Environment in Schools" show a reduction from about 80 % to 55 % in complaints of poor indoor air quality just after renovation, and to 10 % after another year. There was clear accordance between the renovation enterprise with the measured indoor climate and the pupils own opinion of the working environment. Norwegian authority has set a limit of CO2-concentration to 1000 ppm, and our results indicate that the amount of outside air has to be 9 Vs per person to be sure of getting under this limit.