Peters Thomas M, Anthony T Renée, Taylor Craig, Altmaier Ralph, Anderson Kimberley, O'Shaughnessy Patrick T
The University of Iowa, Occupational and Environmental Health Iowa City, IA, USA.
Ann Occup Hyg. 2012 Nov;56(9):1080-90. doi: 10.1093/annhyg/mes050. Epub 2012 Aug 16.
Dust mass concentrations, temperatures, and carbon dioxide concentrations were mapped in a modern, 1048-pen swine gestation barn in winter, spring, and summer.
In each season, two technicians measured respirable mass concentrations with an aerosol photometer and temperatures and carbon dioxide concentrations with an indoor air quality monitor at 60 positions in the barn. Stationary photometers were also deployed to measure mass concentrations during mapping at five fixed locations.
In winter when building ventilation rates were low (center-barn mean air velocity=0.34 m s(-1), 68 fpm) to conserve heat within the barn, mass and carbon dioxide concentrations were highest (mass geometric mean, GM=0.50 mg m(-3); CO2 GM=2060 ppm) and fairly uniform over space (mass geometric standard deviation, GSD=1.48; CO2 GSD=1.24). Concentrations were lowest in summer (mass GM=0.13 mg m(-3); CO2 GM=610 ppm) when ventilation rates were high (center-barn mean air velocity=0.99 m s(-1), 196 fpm) to provide cooling. Spatial gradients were greatest in spring (mass GSD=2.11; CO2 GSD=1.50) with low concentrations observed near the building intake, increasing to higher concentrations at the building exhaust.
Mass concentrations obtained in mapping were generally consistent with those obtained from stationary monitors. A moderately strong linear relationship (R2=0.60) was observed between the log of photometer-measured mass concentration and the log of carbon dioxide concentration, suggesting that carbon dioxide may be an inexpensive alternative to assessing air quality in a swine barn. These results indicate that ventilation can effectively reduce contaminant levels in addition to controlling temperature.
对一座现代化的、拥有1048个猪栏的母猪妊娠舍在冬季、春季和夏季的粉尘质量浓度、温度及二氧化碳浓度进行测绘。
在每个季节,两名技术人员使用气溶胶光度计在猪舍内60个位置测量可吸入颗粒物质量浓度,并使用室内空气质量监测仪测量温度和二氧化碳浓度。还部署了固定光度计在五个固定位置进行测绘时测量质量浓度。
冬季,为了在猪舍内保存热量,建筑通风率较低(猪舍中心平均风速 = 0.34米/秒,68英尺/分钟),此时粉尘质量和二氧化碳浓度最高(质量几何平均值,GM = 0.50毫克/立方米;二氧化碳GM = 2060 ppm),且在空间上分布较为均匀(质量几何标准偏差,GSD = 1.48;二氧化碳GSD = 1.24)。夏季通风率较高(猪舍中心平均风速 = 0.99米/秒,196英尺/分钟)以提供降温,此时浓度最低(质量GM = 0.13毫克/立方米;二氧化碳GM = 610 ppm)。春季的空间梯度最大(质量GSD = 2.11;二氧化碳GSD = 1.50),在建筑物进气口附近观察到低浓度,在建筑物排气口处浓度升高。
测绘中获得的质量浓度通常与固定监测仪获得的浓度一致。在光度计测量的质量浓度对数与二氧化碳浓度对数之间观察到适度强的线性关系(R2 = 0.60),这表明二氧化碳可能是评估猪舍空气质量的一种廉价替代方法。这些结果表明,通风除了控制温度外,还能有效降低污染物水平。