Effects of Climatic Parameters on Formaldehyde Concentrations in Indoor Air

Abstract

The results of measurements of indoor air formaldehyde concentrations in occupational and private residences are presented for the period 1986 to 1993, based on requests of persons who complained about irritations. In many cases, climatic parameters such as the air exchange rate, temperature and relative humidity were also monitored. Calculated mean values for temperature and humidity were 22°C and 45% respectively. The average air exchange rate was 0.36 h−1, which is well below a recommended guideline value of 0.8 h˜' and it was evident that the ventilation is clearly insufficient in many rooms. The average formaldehyde concentration was 119 μg/m −3 (252 data), which is only slightly below the German guideline value of 125 μg/m −3. In 31% of the cases this guideline was exceeded. As expected, a clear relation between formaldehyde concentrations and the air exchange rate was found. The highest levels result at AE≤0.8 h−1, but only a single value exceeds 125 μg/m −3 at AE≥0.8 h−1. The association of law ventilation rates with high formaldehyde levels is also evident from a comparison with theoretical data after normalization to AE=0.8 h−1, using the Hoetjer‐equation. It was also observed that the calculated annual mean concentrations decreased from 1986 to 1993.

Air Change Measurements Using Tracer Gases: Methods and Results. Significance of air change for indoor air quality

“…The 50 th percentile (median) of the ACR was 0.2 h -1 with a 95% confidence interval (CI) of 0.17 h -1 -0.24 h -1 ; arithmetic mean was 0.31 h -1 (95% CI 0.27 h -1 -0.36 h -1 ) and geometric mean was 0.22 h -1 (95% CI 0,20 h -1 -0,25 h -1 ), respectively (see Table 10). Thus, our studies essentially confirm the results obtained by Münzenberg (2004) and Salthammer et al (1995), who conducted ACR measurements under similar methodological conditions in Germany, and received results consistent with those from surveys in Scandinavia by Andersen et al (1997); Bornehag et al (2005) and Harving et al (1992).…”

“…Generally insufficient fresh air supply resulted in an considerable increase of indoor air pollutants. This is the case for formaldehyde (Li et al, 2002;Salthammer et al, 1995;Wegner, 1983) and other volatile compounds (Hodgson et al, 2003) as well as for the radioactive noble gas radon (Andersen et al, 1997;Chao et al, 1997;Sentikova, 1999). Our own studies also found a correlation between the concentration of volatile organic compounds and the ventilation rate in naturally ventilated rooms, as described below.…”

Review of some effects of climate change on indoor environmental quality and health and associated no-regrets mitigation measures

“…Dust mite allergen is associated with allergies and asthma [118]. The risks of indoor dampness and mold growth, associated with respiratory and asthma symptoms [40] are diminished by avoiding high indoor humidity values and the indoor levels of formaldehyde will be reduced because indoor formaldehyde emission rates decrease with decreased indoor humidity [119]. On the other hand, during the heating season when the moisture content of indoor air is often higher than the moisture content of outdoor air, envelope air tightening, without compensating measures, will increase indoor air humidity.…”

Ventilation Control of Volatile Organic Compounds in New U.S. Homes: Results of a Controlled Field Study in Nine Residential Units

“…New homes typically have the highest concentrations of formaldehyde and other VOCs that are emitted from new building materials or new furnishings brought into the home (Dingle and Franklin 2002;Park and Ikeda 2006). Homes with lower outdoor air exchange rates, a condition that occurs when building envelopes are tightened to reduce uncontrolled infiltration, also typically have higher concentrations of VOCs from indoor sources (Salthammer et al 1995).…”