Emenius G, Korsgaard J, Wickman M
Department of Environmental Health, Stockholm County Council, Sweden.
Clin Exp Allergy. 2000 Mar;30(3):418-25. doi: 10.1046/j.1365-2222.2000.00761.x.
The aim of this study was to investigate whether window pane condensation and indoor vapour contribution >/= 3 g/m3 could be used as indicators of defective air change rate, high indoor humidity and high mite allergen concentration in mattress dust.
Actual ventilation rate, indoor temperature, air humidity (AIH/RH) and concentrations of mite allergen were measured in 59 houses and compared with received outdoor temperatures and air humidity. Indoor vapour contribution defined as the difference between the indoor and the outdoor vapour concentration was calculated. Sensitivity, specificity, predictive values and accuracy were calculated for window pane condensation and high vapour contribution (>/= 3 g/m3), as indicators of defective ventilation (< 0.5 ACH), high indoor humidity (>/= 7 g/kg and >/= 45% RH) and high mite allergen concentration in mattress dust (>/= 2 microg/g).
All houses with high humidity and high mite allergen concentrations were positive for the two indicators (high sensitivity), but with a specificity of only 50% so that half of the houses with reported condensation and high vapour contribution turned out to be low pollution houses with adequate high ventilation levels. Both indicators had high negative predictive values and absence of the two indicators almost certainly (97-100%) excluded high indoor pollution with high humidity and high mite concentrations. Overall more than 70% of the dwellings were correctly classified by the two indicators.
Absence of window pane condensation on double-glazed windows and low indoor vapour contribution (< 3 g/m3) during the winter are true markers of a dwelling without high indoor air humidity and without high mite allergen concentrations in mattress dust in houses in a cold temperate climate with subzero outdoor temperatures. The presence of the two indicators is associated with a 18-45% risk of high humidity and mite allergen concentrations so in this latter group further measurements are needed for correct classification.
本研究旨在调查窗玻璃结露以及室内水汽贡献≥3 g/m³ 是否可作为换气率不足、室内湿度高和床垫灰尘中螨虫过敏原浓度高的指标。
在59所房屋中测量实际通风率、室内温度、空气湿度（绝对湿度/相对湿度）和螨虫过敏原浓度，并与实测的室外温度和空气湿度进行比较。计算室内水汽贡献，其定义为室内和室外水汽浓度之差。计算窗玻璃结露和高水汽贡献（≥3 g/m³）作为换气不足（<0.5次/小时换气次数）、室内高湿度（≥7 g/kg且≥45%相对湿度）和床垫灰尘中高螨虫过敏原浓度（≥2 μg/g）指标的敏感性、特异性、预测值和准确性。
所有湿度高和螨虫过敏原浓度高的房屋这两个指标均呈阳性（高敏感性），但特异性仅为50%，因此报告有结露和高水汽贡献的房屋中有一半是污染程度低且通风良好的房屋。这两个指标均具有高阴性预测值，两个指标均不存在几乎可以肯定（97 - 100%）排除了高湿度和高螨虫浓度的室内高污染情况。总体而言，超过70%的住宅通过这两个指标得到了正确分类。
在室外温度低于零度的寒冷温带气候地区，冬季双层玻璃窗上没有窗玻璃结露且室内水汽贡献低（<3 g/m³）是房屋室内空气湿度不高且床垫灰尘中螨虫过敏原浓度不高的真实标志。这两个指标的存在与18 - 45%的高湿度和螨虫过敏原浓度风险相关，因此对于后一组需要进一步测量以进行正确分类。
