By Megan Thom
Staff Writer

Eight panelists make good use of their noses through a study in the Agricultural and Biological Engineering Building, measuring the amount of odor in manure samples.

Helping to improve the air quality of residents living near farms, each panelist judges the acceptability and intensity of odor in various samples of manure.

"The issue of air quality is a problem all over the country," said Albert Heber, associate professor of agricultural and biological

engineering. "We can use the human nose to test concentration of odor inside these bags."

Before this study takes place, air samples are collected from manure reactors and then placed in Tedlar bags, appearing like clear, plastic bags except the odor doesn't stick to them. The air—trapped samples then join the olfactometer, a machine diluting odorous air by using certain amounts of both odorous and clean air.

The air samples become less diluted with clean air throughout this odor-evaluation process, until half of the panelists detect an odor. After smelling two air streams of clean air and another with the odor, these odor detectors rate acceptability from negative 10 to positive 10, from most offensive to most pleasant, respectively.

The intensity of the odor is measured from one to five, with five indicating the highest level of odor. These ratings affect the lives of many people.

"We want to help with the nuisance of odor to residents living near farms," said Heber. "Because larger farms bring more odor, protests about odor threatens farm expansion."

Although the agricultural air quality lab hired 35 panelists for its many tests of air quality, each study only uses eight of them. The lab receives manure samples from various companies such as the Animal Science Department of Purdue and The National Pork Producers.

The first eight to respond to the lab's request for help get the job for that particular study. The odor detectors are paid $30 for each study, lasting about three hours. Each panelist steps up to the olfactometer to inhale the air samples every 10 to 15 minutes.

"You get paid for two to three hours of work, but you can still read at the same time," said Jayaram Balasubramanian, a Purdue graduate student.

Anyone can participate in this on—going project. The panel includes Purdue students as well as residents of Lafayette.

"Interested individuals should contact us," said Heber. "It's something you can joke about, but we do need people who will be serious."

For more information, contact Heber at 494—1214.