Discusses in general terms the problem with formaldehyde in schools in Cologne, reported by Deimel (abstract no.803). Considers problems of ventilating school buildings to reduce the concentration of formaldehyde. Discusses toxicity of formaldehyde and reports a survey of 37 children from one of the Cologne schools. Measurements of formic acid and formaldehyde in the childrens' urine were made after 7 hours of exposure and after 17 exposure-free hours. Concludes that current standards should be adhered to.

Reports measurements of formaldehyde in four newly-built schools. In one school, one year after opening during the hot summer of 1976, concentrations of formaldehyde between 0.3 and 0.9ppm were measured. In another school the average concentration for almost all rooms was over the maximum for working places of 1ppm. The cause was emanation from ceiling and furniture and concentration depended on humidity, temperature and ventilation rate.

Reports investigation of the limiting conditions that produce frosting on air-to-air heat exchangers. Also determines the adequacy of provisions for the prevention of frosting and ice buildup. Four types of heat exchanger were investigated as part of a more general investigation of the operating characteristics of air-to-air heat exchangers. Also reports investigation for various types of energy recovery systems of the cross leakage or contamination of the fresh air by the exhaust air.

The performance of an HVAC system's air-to-air energy recovery exchanger is defined primarily by the exchanger's effectiveness and pressure drop. The effectiveness is dependent on several parameters such as the supply and exhaust mass flow rates and the energy transfer characteristics of the device. Because of this combination, performance data must be established for each individual type of device.

Describes the development and qualification of a test facility for providing a uniform method for testing all types of HVAC air-to-air energy recovery systems. Describes test method. The facility can be used to test coil-loop (closed run-around) heat exchangers, twin-tower (open run-around) enthalpy type exchangers, heat pipe exchangers and plate type exchangers with air flowrates of up to 1900 l/s.

Describes and discusses the principles, advantages and disadvantages of several types of air-to-air energy recovery devices, including the open and closed run-around systems; the heat pipe exchanger; the thermal wheel and the heat exchanger. Places emphasis on the potential energy savings in heating and cooling equipment and fuel costs by recovering energy from exhaust air before it is thrown away. Results indicate annual energy savings of up to 23% with even larger savings in the size of the heating and cooling equipment.

Describes a sampling system developed to collect, analyze and identify organic contaminants in air over as wide a range of molecular carbon number range as possible. Describes sampling technique and reports results of sampling in 36homes in the Chicago area. Two samples were taken simultaneously inside and outside. Fifteen homes were sampled in both summer and winter.< Concludes that people are exposed to a wide range of organic compounds on average at concentrations of below 100ppb.

By observing animal housing in severely cold conditions it was realised that an airtight building with mechanical ventilation did not provide the optimum solution, but better results were obtained from porous buildings. Reports aninvestigation made on a large model building simulating the humidity and temperature conditions in animal housing during winter. The model had a porous ceiling of flax straw.

Describes different goals of air leakage measurement with corresponding measuring methods. Discusses results and experience from measurements carried out with the stationary overpressure method and the non-stationary tracer gas method. Adds working diagrams. Pleads for further standardisation of thespecific equivalent leak opening (SELO) especially of temperature on which it is based. Gives numerical example for calculating the lower limit of admissible non-tightness of cold rooms.

Discusses standards and testing procedures for window air and water tightness. Describes apparatus used at the Technical Centre for Wood. Gives brief results of airtightness tests on 70 windows of different types subjected to a pressure of 10mm of water and of water tightness tests on 40 windows. Describes a test wall, designed to enable "hurricane" tests to be made. Appendices giveinformation on precipitation in France and discuss water-proofing products.