Accuracy and development of tracer-gas measurement equipment.

1979 a project was launched at Technological Institute, Copenhagen with the purpose of developing a method for continuous measurement of air change rates in occupied dwellings. Today - 10 years later - we can introduce the first generation of mass-produced measuring equipment performing measurements of air change rates employing the method of constant concentration of tracer gas. The principles used in the first model, which was introduced 1981, are largely identical to those used in the latest model.