Validated instruments are not available to assess the residential characteristics. The aim of this study was to assess the reliability and validity of an interviewer-administered home visit report. The validity of 48 items in the Home Visit Report was examined against: observations made by a researcher, measurements of relative humidity, cat allergen, and ergosterol, a biomarker of fungal exposure and a biochemical test. Test-retest reliability of 10 fixed residential characteristics was assessed comparing the responses obtained in the main study with the pilot study.

In the past two decades, a group of health problems related to the indoor environment - generally termed sick building syndrome (SBS) - has emerged. We present an investigation of S BS in employees of a ministry working in a naturally ventilated office building that formerly had been used by a pharmaceutical company. A preceding environmental monitoring had failed to identify the cause(s) for the complaints. We conducted a questionnaire-based investigation and categorized the building sections and rooms according to their renovation status and their former use, respectively.

The aim of the study was to describe how allergies and non-allergies perceive the same environment. All high school students in a town in southern Sweden were invited to answer a questionnaire concerning allergy, subjective symptoms, annoyance reactions and perception of the environment (response rate: 81%). The results show that only 45% of the students were nonallergic (n=1,715). Since the symptom frequency among non-allergic students was normal, the schools were classified as healthy.

To achieve a high standard of indoor air quality for new building requires a special knowledge of emissions from materials, design of ventilation systems as well as construction practice. Besides regulations, common rules and instructions are needed to be obeyed to achieve a good result. Classification of cleanliness of new ventilation systems is a voluntary document which determines the cleanliness of classified components produced by manufacturers.

Having paid out a great deal of money to have his ventilation system cleaned the client is entitled to ask 'what do I do next. This short presentation will attempt to answer this question by way of a series of recommendations based on over 40 years experience in Building Services Engineering. The recommendations that I shall make will cover the following points:

Inner surfaces of the supply air delivery system are part of the indoor surfaces. This and technical performance make it important that cleaning of a HV AC system should be included in a proper maintenance program. Research work and cleaning actions have been done in many countries, however, the methods to verify the cleanliness varies and they seem to measure unequally the cleanliness. Filter sampling method is the most used method for determination of dust and debris amount on the surface.