Anthony T Renée, Yang Anthony Y, Peters Thomas M
University of Iowa.
J Agric Saf Health. 2017 Nov 20;23(4):247-263. doi: 10.13031/jash.12426.
This study examined the effectiveness of engineering controls to reduce contaminant concentrations in a swine farrowing room during winter in the U.S. Midwest. Over two winters, changes in air quality were evaluated following installation of a 1700 m3 h-1 (1000 cfm) recirculating ventilation system to provide 5.4 air exchanges per hour. This system incorporated one of two readily available dust control systems, one based on filtration and the other on cyclonic treatment. A second treatment evaluated reductions in carbon dioxide (CO2) associated with replacement of standard, unvented gas-fired heaters with new vented heaters, installed between the two winter test periods. The concentrations of carbon monoxide and hydrogen sulfide were negligible in the test room. Although concentrations of ammonia increased over each winter test period, the increase was unrelated to increased air movement from the new recirculating ventilation system. The dust concentrations were significantly reduced by the ventilation system for both inhalable dust (23% to 44% with filtration, 33% with cyclone) and respirable dust (32% with filtration, 20% with cyclone), significant (p 0.024) for all except respirable dust using the cyclone (p = 0.141). The filtration unit is recommended to improve livestock building air quality because it was more effective than the cyclone unit at reducing respirable dust. Carbon dioxide concentrations were significantly lower with vented heaters (mean = 1400 ppm, SD = 330 ppm) compared to unvented heaters (mean = 2480 ppm, SD = 160 ppm). A 940 ppm reduction in CO2 was attributed to the use of the vented heater, after accounting for differences in outdoor temperatures and animal housing over both test periods. The benefits of readily available technology to significantly reduce concentrations of dust and CO2 demonstrates useful control options to improve air quality in swine buildings.
本研究考察了工程控制措施在美国中西部冬季降低母猪分娩舍污染物浓度方面的有效性。在两个冬季期间，安装了一台1700立方米/小时（1000立方英尺/分钟）的循环通风系统以实现每小时5.4次换气后，对空气质量变化进行了评估。该系统采用了两种易于获得的粉尘控制系统之一，一种基于过滤，另一种基于旋风处理。第二项处理措施评估了在两个冬季测试期之间安装新型通风加热器替代标准的无通风燃气加热器后二氧化碳（CO₂）浓度的降低情况。测试室内一氧化碳和硫化氢的浓度可忽略不计。尽管每个冬季测试期氨浓度都有所增加，但这种增加与新型循环通风系统增加的空气流动无关。通风系统显著降低了可吸入粉尘（过滤方式降低23%至44%，旋风方式降低33%）和可呼吸粉尘（过滤方式降低32%，旋风方式降低20%）的浓度，除了使用旋风方式的可呼吸粉尘外（p = 0.141），其他所有情况均具有显著性（p < 0.024）。建议采用过滤装置来改善畜禽舍空气质量，因为它在降低可呼吸粉尘方面比旋风装置更有效。与无通风加热器（平均值 = 2480 ppm，标准差 = 160 ppm）相比，有通风加热器时二氧化碳浓度显著更低（平均值 = 1400 ppm，标准差 = 330 ppm）。在考虑了两个测试期室外温度和动物饲养情况的差异后，二氧化碳浓度降低了940 ppm归因于使用了通风加热器。易于获得的技术能够显著降低粉尘和二氧化碳浓度，这表明了改善猪舍空气质量的有效控制方案。
