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 CO2, H2O and CO content of the indoor and outdoor air in the four libraries of the University of La Coruiia (Spain) was monitored for 48 hours. For this a multipoint monitoring system was used, based on the infra-red photo-acoustic spectroscopy technique. This allowed us to identify the conditions of air renovation of indoor air with natural ventilation. Although good outdoors air quality was observed, the indoor air quality, on the other hand, was seem to deteriorate considerable during the periods of occupation.
This paper involves assessing radon concentrations at the heating, ventilating and air conditioning (HV AC) environment of Hong Kong University of Science of Technology (HKUST). Ninety rooms with various configurations were selected at random and evaluated in detail. A time-integrated active sampling instrument as well as a passive activated charcoal canister radon detection system were used for the study. With the central HV AC system in the normal operating mode, data on location characteristics, as well as average and peak radon concentrations were collected and analysed.
This paper describes the management of radon concentrations at the Hong Kong University of Science and Technology (HKUST). Applying our derived specific modification factor in the radon concentration predictive mathematical models, we were able to accurately estimate radon concentrations under different conditions of Heating, Ventilating and Air conditioning (HV AC) operations. Various combinations of HV AC operating schemes were tested mathematically. Many possible combinations demonstrate optimal effects.
This paper reports on the experimental results using a standard room chamber to evaluate the impact of various parameters on indoor radon concentrations. The paper assesses the suitability of using pro-existing mathematical models for the prediction of indoor Volatile Organic Compounds (VOC) to estimate radon concentrations in the heating, ventilating and air conditioning (HV AC) environment. A test chamber study was conducted to thoroughly evaluate and validate parameters considered in these models.
Full-scale experiments were made in a displacement ventilated room with two breathing thermal manikins to study the effect of movements and breathing on the vertical contaminant distribution, and on the personal exposure of occupants. Concentrations were measured with tracer gas equipment in the room and in the inhalation of both manikins. Tracer gas was added in the heat plume above a sitting manikin, or in the exhalation through either the nose or the mouth. The other manikin moved back and forth at different speeds on a low trolley.
Two series of formaldehyde concentration measurements were conducted on the first storey of a medium size, three-storey, naturally ventilated office building. In this building, due to extensive renovations, a variety of formaldehyde containing materials were used. In the first data set, just after the end of work, values of up to 0.4 ppm were recorded. Higher concentrations were encountered in the internal rooms. In the second data set, nearly one month later, formaldehyde concentrations did not exceed 0.2 ppm.
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.
Thermal performance of the floor-supply displacement ventilation system was evaluated in a large climatic chamber designed to simulate a single span of an office building. Detailed measurements were conducted to determine the indoor environment and skin temperature of a thermal manikin Temperature gradient in the room could be kept smaller, compared to conventional wall-supply unit displacement ventilation system, owing to the floor cooling effect of the floor-supply system.
Login