An interdisciplinary team of Georgia State University scientists has received a $1.2 million grant from the U.S. Department of Agriculture to develop and test a new radon gas measurement system in metro Atlanta.
The four year project, entitled SitS: A Novel Large-Scale Radon Measurement Wireless Testbed for Spatio-Temporal Study of Radon in Surficial Soil, is a global first, said project director Ashwin Ashok, an assistant professor of computer science.
“Nothing like this network is available anywhere in the world,” said Ashok. “This test bed will measure radon gas continuously, 24 hours a day, seven days a week and the data can help builders plan mitigation efforts ahead of time.”
North Georgia, including the Atlanta area and its suburbs, is a region where bedrock is prevalent and is well known for its high natural rates of radon.
Radon is an odorless, radioactive gas that is produced as naturally occurring uranium in the soil decays. Outdoors, it disperses and presents no risk. Indoors, however, the gas can infiltrate homes and other buildings and is the second leading cause of lung cancer, after cigarette smoking. Exposure to radon gas kills nearly 22,000 people a year in the United States, including 800 in Georgia, according to the state’s Consumer Protection Division.
Exposure to indoor radon gas is estimated to cause up to 20 percent of lung cancer deaths, other researchers have found.
Current approaches to radon attempt to measure and mitigate after building, using certified radon mitigation contractors. A radon level of less than 4 picocuries per liter is considered safe for human health.
The research team will create a system to measure radon gas underground in real time in DeKalb County using a 200-node wireless sensor network consisting of battery-operated devices placed underground. DeKalb County, with a population of 6 million, is at high risk for radon exposure.
“We will learn how radon percolates through the entire geological stack of rock and soil,” Ashok said, “from the underground to the surface. There is no clear understanding of that currently, and no mathematical model to predict it.”
The system will use 200 devices at 200 different locations, all connected to the Internet. The monitoring devices will be placed from one to 10 feet underground, capturing readings from shallow to deep soil.
Before securing the grant, the interdisciplinary team collected indoor home radon measurements across 200 locations in DeKalb County, confirming radon emissions cluster in specific areas in the county.
“We plan to begin measurements with typical off-the-shelf devices you can find in stores,” Ashok said. “However, we may need to customize them for the kind of performance, resolution and accuracy we need.”
The measurement data will be made available to the community for free.
Ultimately, says Ashok, this kind of system could be deployed globally, in any area of the world with radon risk. It might be useful for assessing risk ahead of residential and commercial building, as well as determining the hazard in underground mining operations.
The interdisciplinary project includes Georgia State geologist Daniel Deocampo, geographic information sciences expert Dajun Dai, soil scientist Nadine Kabengi, geophysicist Brian Meyer and nuclear physicist Xiaochun He, as well as collaborators at the British Geological Society and the University of York. Team members will also develop undergraduate course modules to enable Georgia State students to participate in the research and be exposed to cross-disciplinary learning.