We gathered exposure data on indoor air pollution and investigated the dose-response slopefactor for indoor air pollutants, such as volatile organic compounds, aldehydes and radon.Population cancer risks (that is the theoretical cancer deaths) were estimated from exposure tothe pollutants. In addition, the damage costs, due to their risks, were estimated usingwillingness to pay and value of a statistical life, which were investigated by a dichotomouscontingent valuation method.

In some indoor environment surveys, respondents are asked to recall conditions acrossseasons (e.g. to recall summer conditions during a winter survey). This study assessed thereliability of such recall, based on a survey of 728 people in 12 UK office buildings. In bothwinter and summer, the questions addressed both summer and winter conditions, andbuilding-related symptoms. Correlations were calculated between equivalent responses ineach season (e.g. odour in winter, as rated in the summer and winter surveys). The bestcorrelated IAQ questions were those concerning specific smells (e.g.

Sick building syndrome (SBS) symptoms were investigated in a laboratory study of low humidity environments: 30 subjects were exposed to clean air at 22C with 5%, 15%, 25% and 35% RH and 30 were exposed to polluted air at 18C, 22C and 26C with a constant moisture content of 2.4 g/kg dry air and at 22C/35%RH. The subjects were exposed to each condition for 5 h and reported the intensity of SBS symptoms. Five hours of exposure to clean air at 5% RH caused only eye symptoms, while 5 h of exposure to polluted dry air at 15% RH aggravated a number of symptoms of the skin, nose, throat and lips.

The particle deposition on ceilings causing the soiling of induction outlets is mainly caused by the features of mixed ventilation.This paper offers a solution to the problem. The search for a clean outlet is made easier with the proposed optical and experimental technique that suggest to visualize the soiling patterns of an outlet by photographing deposited sodium chloride crystals. These tracer-particles stem from an atomizer and aerodynamically behave like the particles responsible for the soiling of ceilings in reality.

Today, tracer gas is used as a reliable means to examine various queries related to mechanical systems. Prerequisite is the safe and routine handling of the relevant analysis methods. Apart from some basic considerations, the present paper includes results of ventilation efficiency studies and a comparison of different systems on the basis of characteristic parameters.

Velocity measurements were performed in the air flow resulting from two horizontal opposite air jets along a ceiling. Results show how the air velocity decreases along each of the two air jets, compared to the velocity decrease along a single free air jet.Experimental results are compared with a correlation from the literature. The agreement is good.

Two air terminal devices (ATD) for personalized ventilation (PV) were developed: RoundMovable Panel (RMP) and Headset-Incorporated Supply (Headset). The performance of theATDs was tested at three combinations of room air temperature and supply personalized airtemperature: 23/23C, 23/20C and 26/20C, respectively, and at different flow rates ofpersonalized air, ranging from 5 to 15 l/s for RMP and from 0.18 to 0.5 l/s for Headset. Abreathing thermal manikin was used to evaluate the inhaled air quality achieved with thedeveloped ATDs as well as the performance in regard to thermal comfort.

The concept of personalized ventilation (PV) is at the cutting edge of technologicaldevelopments in the area of air-conditioning and is fundamentally based on improvingventilation to every individual in the built environment. A PV system provides occupants withcontrol so that they can adjust their individual thermal environment as well as achieve goodindoor air quality.

In northern Europe ongoing changes in legislation that require increased levels of insulation,and the sealing of houses to reduce infiltration heat loss, has led to concerns about indoor airquality. As a result there is a need to achieve regulated and energy efficient winter ventilationin houses. The system currently being tested (WHOLE-pvs) in paired (test and control)houses and flats in Denmark, Poland and Ireland uses supply air windows in combinationwith Passive Stack Ventilation.

In time, ventilation ducts and accessories get dirty and this may lead to malfunction of ventilationequipment, fire hazard and especially a decrease in supply air quality. Repeated cleaningof the components can prevent these adverse effects. The frequency of cleaning dependson how easily different components get dirty.