[Connection between air quality and room climate and estimation of dwellings by health-impaired inhabitants]. / Zusammenhang zwischen Luftqualität und Raumklima und der Beurteilung der Wohnung durch gesundheitlich beeinträchtigte Bewohner.

The investigation was performed in winter 1990 and 1991 when measurements were taken in 16 dwellings of patients, recruited from a pulmologic outpatient centre. Patients suffered from repeated respiratory irritations which they attributed to dwelling conditions. Inhabitants reported by means of questionnaires and standardized scales the dwelling situation and their dwelling behaviour, subjective ratings of indoor environmental quality as well as ratings of wellbeing. The load of indoor pollutants (CO2, CO, NO2, HCHO), biological agents (fungal spores, house dust mites) as well as indoor climate factors were assessed. The measurements revealed an evident load at least in one parameter; in the majority of dwellings combined loads of air pollutants and biological agents were apparent. Homes supplied with gas as main energy source had significantly higher concentrations of CO2, CO and NO2. At noon, exposure limits of CO2 and NO2 were frequently exceeded. Inhabitants of homes being supplied with electricity instead of gas gave significantly better air quality ratings. The correlations between the average score concerning the rated health quality of their homes and the rate of excess of exposure limits are significant: The health quality ratings are significantly related to the concentrations of "air quality indicators", which induce the feeling of stale air (CO2) and mucosa irritations (NO2). Ratings of wellbeing are significantly connected to objective parameters, i.e. NO2 baseline load, fungal spores in the air and the difference between wall-air temperature. Our study suggests that people suspecting a connection between their health impairment and dwelling conditions should be taken serious. The measurement program proved to be a suitable screening procedure to assess adverse environmental influences in homes. More homes should be investigated to further support our findings.

Personal light dosimetry in permanent night and day workers.

Light exposure was measured in six day and six night watches (working 12-hour shifts five days in a row) during 48 h on work days and 48 h on days off using a photocell with a sensitivity corresponding to photopic vision. The photocell was mounted on a frame of spectacles, thus measuring in viewing direction. Light exposure was low both in night and day watches; however, in night watches exposures were significantly lower: On work days, night watches spent a mean of 13 min above 1,500 lx, day watches 52 min; on days off, night watches spent 3 min above 1,500 lx but day watches 89 min. Unexpectedly, night watches had no higher exposure during days off. We suspect that this is due to a light avoidance tendency in permanent night workers. High negative correlations between the acrophases of subjective state (e.g., alertness and mood) and light exposure in night watches indicate that bright light would probably increase desynchronization between subjective state, sleep, and activity.

[Effect of various furniture covering fabrics on heat regulation and comfort]. / Der Einfluss verschiedener Möbelbespannungsmaterialien auf Wärmeregulation und Behaglichkeit.

The effects of three different materials for furniture fabrics (wool, polyacrylonitrile and Skai) on thermophysiological parameters and comfort were studied. In a laboratory design male, middle aged subjects were tested three times for three hours in a climate chamber, being exposed to internal and external thermal strains as well as to stress inducing situations. The outcome of this research suggests an essential influence of the structure of the tested materials but only small influences by the kind of fibres. The test situation "Skai" induced markedly different effects on skin temperature, skin moisture level and self rated thermal comfort as compared to both textile materials: A high sweat secretion followed by a continuously increasing moisture accumulation could be observed, especially for areas of the body surface which were tight contact with the material. Simultaneously a distinct skin temperature decrease at the back was found, which can be interpreted as a consequence of a high heat conduction due to the material itself as well as by sweat vaporization when the back was lifted from the backrest. The differences between the natural fibre- and synthetic fibre materials were generally small and occurred merely under heat stress conditions, where a pronounced reactivity of skin temperatures, skin moisture and heart rate could be observed testing the synthetic textile material. Being asked about thermal comfort, the subjects attributed their ratings to uncomfortable room climate conditions rather than to properties of the materials on which they were seated.