Measurements of dark smoke and SO2 concentration made inside and outside a school showed no significant difference in the case of smoke but SO2 concentrations indoors were only 71% of those outside. Holiday periods, when the buildings were unoccupied gave similar results to those periods when thepupils (non-smokers) were present.

Ventilation efficiency involves two aspects, to preserve thermal comfort, draughts should be avoided and yet one tries to obtain the best "sweeping out" which corresponds with a maximum exhaust of contaminants from the occupied zone for a given flow rate.< Reports study of 75 tests of ventilation efficiency made in a climatic roomrepresenting a heated living room. Thermal comfort was tested by measuring the air velocity both in the ventilation jet and in the occupied zone.

Examines various definitions of ventilation efficiency. When using tracer gas techniques the definition of a ventilation system's efficiency can be based on the slope of the tracer gas curve, or the ratio between concentrations, or the area under the curve. Examines the consequences of these definitions for a simple theoretical model. Presents experimental measurements on a test room which show that sometimes very low ventilation efficiency can occur.

Presents a proposal for an Indoor Climate Standard, to be included in the building codes of the nordic countries. The standard comprises two parts: 1) air quality and ventilation, 2) thermal environment. The paper presents and discusses the main features of the two parts of the standard. Mechanical ventilation is required in all buildings including dwellings at a minimum outdoor air change of 0.5/h. Limits for operative temperature and for thermal non-uniformity are given for winter and summer conditions.

Describes an energy audit procedure developed for determining economically optimal retrofits for a residential building. This audit is a microprocessor -based, interactive, site and house specific package addressing conservation, solar and wind measures. A dymnamic model of heating and cooling load is used to evaluate fuel savings. Special attention is given to the estimation of monthly average air infiltration rates, using a model correlating pressurization results with air infiltration under natural weather conditions.

Reports survey of indoor climate problems in dwellings. Questionnaires were distributed to 424 families who had complained of indoor climate problems and 240 replies were received. The questionnaires dealt with complaints relating to the dwellings and the age, profession, health and smoking habits of theoccupants. The dwellings are described by type, age, material of outer and interior walls, ceiling and floor. There are questions on ventilating habits, cleaning habits and occupants' views on dust, noise, odour, temperature, humidity and draughts.

Reports measurements of indoor air quality in an air conditioned California High School over a range of ventilation rates, ranging from 13.3 cu.ft. of outside air per minute for each classroom occupant to approximately 1.5 cfm per occupant. Parameters measured include outside air supply rate, theoccupants' perception of indoor air quality, microbial burden, concentration of CO2, CO, NOx, SO2, O3 in two classrooms, a hall and outdoors.

Discusses organic contaminants in rooms and reviews soviet literature on the subject. Gives a table of maximum permitted concentrations of 59 compounds according to standards of the Soviet Union.