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.
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.
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.
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.
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.
In a room with a raised floor HV AC system (RF system), the vertical temperature gradient became an important factor in relation to the ventilation requ1rement to maintain a vertical temperature difference within a comfort standard such as ASHRAE Standard 55-1992. A series of detailed laboratory experiments were carried out to obtain the design ventilation requirements with various conditions of ventilation rates, cooling loads, and types of floor outlets. The main results are shown as follows.
In some ventilation and dust removing system of workshop, a great deal of energy is wasted due to heated and cooled indoor air being exhausted directly. So if the dust in the indoor air is removed and then recirculate, the objective of energy saving can be reached. In this paper, the calculation equation of dust concentration, relative humidity in indoor and recirculate air and heater capacity are given along with the control measures to them.
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.
Login