Second Leading Cause of Lung Cancer Focus of Project by FSU Engineers
Radon is a colorless, odorless, tasteless gas that is the leading cause of lung cancer among non-smokers - and if you live in the Tallahassee area, there's a one in five chance that there are high levels of radon in your home.
A team of engineering students at Florida State University have been sponsored by the Florida Department of Health to test homes in the Tallahassee area for elevated levels of radon. Of the 42 homes they tested, 45 percent had elevated levels of radon, a radioactive gas derived from the natural breakdown of radium in soil, which then typically comes through the foundation into the building.
The initiative was undertaken as a senior design project by four mechanical engineering students, Chris Vogel, Norman Medina, Eric Levitt and Jason Lynne with the goal of developing a unique system of radon mitigation (meaning 'removal') for a home in the Tallahassee area with elevated levels of radon and design a new building code for non-slab, raised houses. The project has been in development since last fall and will conclude in April of this year.
Vogel said the task of the engineers was largely about standardizing the issue of radon measurement and mitigation.
"What we were brought in to do was kind of put some science and math behind this," said Chris Vogel, a senior mechanical engineering student who worked on the project. "We found a house in northern Tallahassee, and what we're trying to do is design the most effective, cost-efficient system for that house. There are engineers that can do this, and put their stamp of approval on it, but it would easily cost $2,000 to design a specific system for that. So if we can go in and find some sort of generality in it, that's going to help out a lot."
There are two methods of radon mitigation which involve pressurization and depressurization.
"Coming out of the ground around us all the time, it's diluted to extremely low levels in outdoor air," said Clark Eldredge, a radon specialist with the Florida Department of Health and one of the sponsors of the project. "You put a building on the ground, and that building has only a limited volume of air, so it doesn't dilute as much entering the building as it does going in outdoor air. If you can set up a low pressure area below the foundation, instead of radon coming in through the foundation into the building, it enters that low pressure area. Some types of buildings, you can't address the foundation that way, so you end up having to follow dilution as a method for reducing radon levels, so you bring in fresh air or an air exchange system."
The team of engineers elected to use the depressurization method in both mitigation systems they developed, which operates by creating a pocket of lower pressure underneath the structure. According to Vogel, there are some drawbacks to the pressurization method, which works by bringing ambient air into the building.
"One of the major problems with that is you're bringing outside air in and condensation forms very easily," said Vogel. "So every problem you have with condensation - the mold, the mildew - happens with that. It spreads throughout the house. But what that does is redeposit pressure within the house, and that will effectively keep the radon out."
For those concerned with elevated levels of radon, how a building is mitigated is less important than results.
"The general concern here is that people are dying from radon," said Eldredge. "It's just one of the many risks that we face, and one that people can readily control and avoid. Performing radon tests is fairly simple and easy to do. Actions to fix radon problems in buildings again are fairly simple. It's a very avoidable health risk. Our primary goal is to reduce lives lost due to radon."
Radon testing is performed by taking a sample of air and sending it to a lab to analyze the levels of radiation in the sample.
"Four (Pico curies) per liter of air is considered high, which increases your risk of lung cancer," said Vogel. "The statistic is if you're at a level of eight, you're twice as likely to develop lung cancer over a set span of time than a smoker."
The U.S. Environmental Protection Agency estimates that radon is responsible for more than 21,000 lung cancer deaths per year, and according to Eldredge, radon exposure affects all equally.
"There's no specialization for radon," Eldredge said. "There's no higher risk for one person over another. All homes, all types of structures, all types of buildings, all types of neighborhoods are subject to radon problems. There is some overall variability in regions, localized as well as broader."
