Radon Facts

Radon Facts

What is Radon?

Radon is a radioactive gas that can cause cancer. Because radon gas has no smell, is invisible to the naked eye and has no taste, it is considered one of the most deadly forms of gas. The Surgeon General warns that radon gas has been proven to be the second leading cause of lung cancer in the United States.

If you smoke and your home has high radon levels, you're at high risk for developing lung cancer. Some scientific studies of radon exposure indicate that children may be more sensitive to radon. This may be due to their higher respiration rate and their rapidly dividing cells, which may be more vulnerable to radiation damage.

Radon is a naturally-occurring, radioactive gas created when uranium in the earth’s rock, soil or water decays. Indoors it is not naturally occurring, but a result of the way our homes, schools, and workplaces are designed, constructed, and maintained. Radon is one of the most significant environmental health risks that exists today.

Why is Radon Dangerous?

Radon is radioactive. Radon exposure has been identified by the American Lung Association as the second-leading cause of lung cancer in the United States. Outdoors, there is little danger because radon is diluted in the open air. But indoors, radon is trapped and becomes concentrated in enclosed or poorly ventilated spaces.

The only way to know if you have high radon levels is to have your home tested. Radon enters your home in a number of different ways, so it is important to have your home tested and evaluated for radon levels, even if you do not suspect you have a problem.

Radon is a naturally occurring substance, and unfortunately is found in homes all across the United States. Radon is able to seep into your home through even the smallest cracks, floor joints, and even through your basement slab. Since the pressure in the interior of your home is lower than that of the soil surrounding your home, radon is able to seep into your home through the basement slab and foundation.

The basement slab or foundation does not have to be cracked to allow radon to enter, although a crack in the basement wall or home foundation can certainly make the problem worse. The difference in pressure alone can be all it takes for dangerous levels of radon to seep into your home. That difference in pressure acts like a vacuum creating a stack effect, sucking the radon gas from the surrounding soil and environment into the interior of your home. Radon typically enters your home through the basement, then seeps up into the living space, putting yourself, your home and your family at risk.

How is Radon Linked to Lung Cancer?

When you breathe in radon gas, particles settle in your lung tissue and begin to decay. As the radon particles decay, they release bursts of energy that damage the lung tissue cells. Over time the cell damage can lead to the development of lung cancer.

Radon gas decays quickly, the decay gives off tiny radioactive particles. When you inhale the radioactive particles enter and damage cells lining your lungs. Exposure after time can lead to lung cancer. Lung cancer is the one cancer proven to be associated with breathing radon gas. Scientists now estimate that between 15,000 - 22,000 deaths caused by lung cancer each year are related to radon in the United States.

How Does Radon Get into Homes?

All homes have some amount of radon. The question is how much. Since you cannot taste, smell or see radon gas, scientific testing is needed for detection. You can look at a picture of radon risk across the country to see the highest potential zones. Living in a high radon zone does not mean you will necessarily have high radon, nor does living in a guarded radon zone mean you do not need to test.

The presence of radon indoors depends on a number of factors including: building style, geology of the underlying found and climate.

Radon Entry Points

  • Concrete Slabs with cracks
  • Brick walls resting on hollow block foundations with spaces
  • Cracks and pores in blocks of concrete
  • Floor / Wall Joints
  • Soil that is exposed like soil in a crawl space or sump
  • Drain tile draining into an open sump
  • Joints in Mortar
  • Pipe fittings that are loose
  • Tops of block walls that are open
  • Water from a well

About 1 in 15 homes here in the United States have elevated levels of radon. Some areas have more of a radon problem over others, however radon can be found in all areas. To know if your home has deadly radon gas you must test for radon.


Radon Map

This radon map was created to assist national, state, and local organizations to better target internal resources as well as to implement building codes to address radon-resistance. This map is not intended to be used to determine if a home in a given zone should be tested for radon. Homes with elevated levels of radon have been found in all three zones. All homes should be tested regardless of geographic location.