Ventilation control to reduce airborne contaminants.
O'Shaughnessy PT; Thome PS; Donham KJ; Smith TF; Hoff SJ
NIOSH 2002 Mar; :1-10
Studies have shown conclusively that airborne contaminant levels in swine confinements are typically of a sufficient level to pose a health hazard to workers in that occupation. In addition to a particulate component that can reach levels of 26 mg/m3, gases present in confinements in high amounts include methane, hydrogen sulfide, ammonia, and carbon dioxide. Recognized respiratory diseases of swine farmers include upper airway inflammation, an asthma-like syndrome, and chronic airflow limitations. Ventilation systems associated with swine confinements are largely designed to provide a comfortable climate for the pigs. However, because confinements are operated on a for-profit basis, costs associated with operating the ventilation system are typically kept to a minimum by minimizing fan usage, which results in maintaining high airborne contaminant levels. This research involved the analysis of continuous readings of two environmental parameters, temperature and relative humidity, and two air quality parameters, airborne dust and ammonia, relative to measurements taken by standard sampling methods. Results indicated a relatively good correlation between the real-time temperature and humidity recordings and standard sampling methods but low correlation between sensor-based dust and ammonia measurements and those taken by standard method. Therefore, the use of these monitors as direct-reading instruments for feedback control of airflow rates to mitigate concentration levels is suspect. Robust sensors that are easily calibrated and capable of withstanding the harsh environment of a swine confinement are needed. To simulate the effect of airflow on environmental and quality control parameters, computer software capable of simulating dynamic processes was utilized. The resulting model output was compared and validated with the real-time measurements taken on site with results showing a close agreement between the two. Development of models ofthis sort show promise in accurately determining the effect of ventilation through a room or building on the resulting indoor air quality expressed in terms of environmental conditions or airborne hazards.
Control technology; Agricultural workers; Agriculture; Air contamination; Air flow; Air quality measurement; Air sampling; Air sampling equipment; Analytical methods; Animal husbandry; Animal husbandry workers; Respiratory system disorders; Ventilation; Ventilation systems; Temperature effects; Gases
74-82-8; 7783-06-4; 7664-41-7; 124-38-9
Final Grant Report
NTIS Accession No.
Research Tools and Approaches: Control Technology and Personal Protective Equipment
National Institute for Occupational Safety and Health
Department of Occupational and Environmental Health, Institute for Rural and Environmental Health,The University of Iowa, Iowa City, Iowa 52242