Ventilation rates and IAQ in European standards and national regulations

This paper presents some results from the Work Package 5 in the HealthVent project supported by the European Commission. One of the objectives of the project has been to review and critically evaluate the existing requirements on ventilation and IAQ defined in national building codes and European standards. The project’s focus has been set on ventilation rates, pollutants, noise, temperature and draft in dwellings, offices, schools and kindergartens. This paper presents a summary of the values given in European regulations and results of comparisons. The up-to-date data in national legislation and codes were collected from 16 European countries with questionnaires, which were sent to project partners and trusted experts on ventilation. The requirements on ventilation rates were found to be given in different units, therefore test cases of real-life design situations were introduced to compare the data on a basis of a common unit. The results show that the ventilation rates given in the regulations are inconsistent and very heterogeneous. The ventilation rates in test cases range from 0.23 to 1.21 h-1 in dwellings and 4.2 to 41.7 l/s for local exhaust rates. The ventilation rates per person in test cases of classroom, playroom, and office range from 4 to 25 l/s. Big differences were also found in pollutant levels. Limit CO levels range from 3.0 to 12.5 mg/m3 and formaldehyde levels from 10 to 100 μg/m3. Minimum winter air temperature requirements were found in the range of 15 to 21°C, maximum summer air temperatures from 25 to 28°C, maximum air velocity in summer from 0.15 to 0.30 m/s and in winter from 0.15 to 0.25 m/s. Limit maximum noise levels were also found scattered, from 26 to 40 dB(A) in sleeping rooms and 30 to 50 dB(A) in other investigated room types. In conclusion, the evaluation of the data showed that values in the European local regulations, standards, and those practised locally, are very inconsistent. Moreover, several values in regulations were found to be looser than the recommended values published in European standards and WHO guidelines, thus allowing lower ventilation rates and higher pollutant levels than recommended. Results indicate that there is a considerable need on the European level to harmonize the ventilation and IAQ regulations and adjust them to the values provided in standards and guidelines.