A large number of air-conditioned office blocks constructed in recent years in the FRG have been equipped with waste-air ventilated windows. Based on experience now available from planning, laboratory tests and practical operation, describes the different design principles and their technical characteristics. Bases the evaluation on window designs which have been used in 11 office buildings totalling 10000sq.m useful floor area.
Tests a large office building, consisting of several octagonal towers and other blocks in a boundary layer wind tunnel. Determines the highest suction pressures which are relevant for the fixing of the cladding. Uses a tracer gas method to determine recirculation problems of the ventilation system inlets and outlets resulting from the arrangement of octagonal towers of different heights. Wind velocities on the flat roof of some towers are studied by meansof an erosion technique using flour, checks the accuracy of the method using hot wire measurements.
Determines ventilation rates and intercell flow rates in naturally ventilated office building using multiple tracer gases. Subdivides the building into 3zones and seeds each zone individually with a different tracer gas. Monitors the time histories of the concentrations of all gases in each zone using non-dispersive infra red gas analysers. Calculates air flow rates from experimental data.
Describes the retrofitting of a 14-storey office block in Oslo, done as part of an energy conservation project carried out in Norway 1979-82. The main reduction in energy consumption was achieved by tightening air leaks between concrete wall elements and windows by the application of sealing compound in 2 critical types of joint in the facade. Measures the energy consumption one year before and one year after retrofitting, using thermography to find the air leaks and to verify the tightening afterwards. Also carries out pressurization tests using the building's ventilation system.
Describes the testing of 8 federal office buildings (size from 3000 sq.m. - 45000 sq.m.) for their air infiltration characteristics, as part of the NBS program to develop diagnostic test methods for evaluating the thermal integrity of federal office buildings. Performs tracer gas tests in the autumn, winter and spring to evaluate both the ventilation of these buildings during occupied periods and the natural air leakage under various weather conditions.
Reports the results of measurement of ventilation efficiency in a full scale model of a small office with a diffuse air supply, which can be used to improve ventilation efficiency and therefore reduce air supply rates. Steady state and transient definitions of ventilation efficiency are given. Finds that ventilation efficiency depends on air flow rate and heat gain in the office. Higher air flow rates give lower pollutant concentration in the ocupied zone but also more mixing between the occupied and under-ceiling zones.
Despite having balanced mechanical ventilation, a large number of modern buildings in Sweden have unsatisfactory indoor climate. Problems include mould, irritation of the eyes, nose and throat, skin rashes, feelings of dryness, hoarseness andheadaches. To control ventilation according to requirements the right indicator variable must be selected and the system must permit the proper control in the occupied zones. Measurements of air pollutants were carried out outside and inside a mechanically ventilated office building.
Parts 2 and 3 of a series of articles. Describes office buildings with natural and mechanical ventilation systems mentioned in part one, where the mechanical ventilation plus humidification and cooling is used only during the coldest parts of the winter and hottest parts of the summer. Provides comparative cost analysis for the building. Discusses design criteria to take account of fullor part time natural ventilation. Treats maximum room depths, window types,external and internal doors, furniture, room layouts.
Notes the large savings possible if ventilation were adapted to the prevailing need. A promising possibility for indicating occupancy and thus the ventilation requirement is measuring the level of carbon dioxide. The project includes a test with equipment for CO2-monitoring of the exhaust air flow in an office building which controls the volume of outdoor air supply, thusmaintaining the CO2 level constant. Measures how the CO2 level can vary locally,how other pollutants in air can vary, how much energy can be saved.
Undertakes experimental studies to identify antecedent conditions of various health and comfort problems experienced by office workers in sealed, air conditioned buildings in New York City and Vancouver. Tries to relate building characteristics (paricularly of lighting and ventilation) to prevalence andincidence of reported health and comfort problems. Finds that changing both lighting and ventilation simultaneously results in a 31.2% reduction in reported eye irritation.
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