English

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.

Compares and contrasts different methods of ventilation measurement in large buildings. Conventional methods of using tracer gas to measure ventilation rates in large volumes are cumbersome and expensive. These constant concentration and decay measurements require artificial mixing, complex monitoring equipment and large installation costs. By using discrete injection and sampling units, long term samples of tracer gas be collected with the minimum of capital and installation costs. Samples collected represent the mean local equilibrium tracer gas concentrations.

States that methods used by Swiss energy consultants in calculating air change rates are often inaccurate. Most consultants use the "observation method" utilising smoke pencils etc. and mistakes are made in calculating conditions causing air infiltration. Describes a new graphic method for estimating mean air change rates, which needs data on construction, pressurization values and window opening.

Reviews the published data on component air leakage, and from this compiles a set of component leakage figures for use in estimating leakage areas and their distribution in buildings. These calculations are compared with measurements of leakage areas in 36 houses in different locations in the US. The model predicts leakage area accurately for the average of the 36 houses, while for individual houses the standard deviation is about 20%. Discusses the assumptions and methods to convert other types of component leakage data to component leakage area.

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.

A short treatment of the concepts and aspects that play a role in ventilation is followed by a brief description of the investigation methods employed. Gives a concise survey of the equipment and mathematical models used. Reviews the ventilation research carried out by the IMG-TNO. Covers factories, laboratories, hospitals, auction halls and similar buildings.

Measures the airtightness of various types of 25 residential units (9 detached houses and 16 apartments) using the fan pressurization technique. Shows the relationship between the pressure difference across the building envelope and the volumetric flow rate of air as well as the ratio of the effective leakage area of one building element to the total leakage area. Compares the airtightness of various types of houses in different countries using the valueof the effective leakage area per floor a at a pressure difference of 10 Pa.

Describes pressurization tests conducted by the National Testing Institute on 3 large industrial buildings. Sets out equipment and methods used including atracer gas method to calculate air flow through the fan rather than the usual measuring duct. Gives construction and volume details of buildings measured.

Reviews air infiltration studies in New Zealand. Tighter houses have evolved over the years through changes in building methods and materials. Some of the tighter houses can have condensation problems. Investigates the airtightness of 40 houses together with the leakage resistances of a range of building components and bulk sheathing materials. A comparison with houses in other countries shows that comparatively tight houses can arise from simple construction methods not employing vapour barriers. Gives air infiltration rates as a function of windspeed for 4 of the 40 houses.