Using olfactometry to measure intensity and threshold dilution ratio for evaluating swine odor.

North Carolina Department of Environment and Natural Resources, Division of Air Quality, Fayetteville, USA.
Journal of the Air & Waste Management Association (1995) (Impact Factor: 1.17). 08/1999; 49(7):847-53. DOI: 10.1080/10473289.1999.10463855
Source: PubMed

ABSTRACT Intensity and threshold dilution ratio are two important indices for odor control of swine buildings. Although odor threshold dilution ratio is a widely used index to describe an odor, it should be related to intensity to be more useful. A method was proposed to measure both indices simultaneously by using a dynamic forced-choice olfactometer. Four air samples were taken from each of four swine rooms including farrowing, finisher, gestation, and nursery. A panel of eight people was used to evaluate odor intensity. Odor threshold dilution ratios were calculated according to the American Society for Testing and Materials (ASTM) Standard Practice E679-91 to be 333, 424, 25, and 221 for samples collected from farrowing, finisher, gestation, and nursery rooms, respectively. After the samples were diluted 14.7 times, the odor intensities were evaluated to be 3.79, 3.46, 0.48, and 4.0 for the above-mentioned rooms, respectively. The data collected were used to develop a mathematical model.

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    ABSTRACT: This study developed and tested a protocol for monitoring odors near a Concentrated Animal Feeding Operation (CAFO). The Nasal Ranger, a portable field olfactometry instrument, was used by a panel of trained individuals to conduct the monitoring near a swine CAFO. Monitors were selected based on olfactory sensitivity, scheduling availability, and lack of association with the CAFO or residential neighbors of the CAFO. Monitors were trained to use the Nasal Ranger, collect and record weather data, and characterize any odors detected. Data were collected over a 3-year period (2007-2009) for approximately 9 months each year. The data recorded included odor intensity, a description of the odor, date and time of the reading, and weather conditions. Of more than 50,000 readings, forty-one (0.1%) odor readings had a dilution to threshold ratio (D/T) of +/- 7:1 and were attributed to hog manure. The frequency of odor readings attributed to hog manure with D/T +/-7:1 was found to negatively correlate with log wind speed and positively correlate with wind from the direction of the farm. Other meteorological variables (temperature, precipitation, cloud cover) and time of day did not influence the frequency.
    Journal of the Air & Waste Management Association (1995) 12/2011; 61(12):1398-408. · 1.17 Impact Factor
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