HOMEOWNER’S 

AND RENTER’S 

GUIDE TO REDUCING 

RADON AFTER 

DISASTERS 
HOMEOWNER’S AND RENTER’S GUIDE TO REDUCING RADON AFTER DISASTERS

While natural disasters usually won’t change your long-term radon risk, they can provide opportunities to install 

radon-resistant features. Installing a radon reduction system during rehabilitation or rebuilding, such as after a 

disaster, can make installation easier and less expensive. 

WHY WE SHOULD WORRY ABOUT RADON 

•		 Radon is a cancer-causing, radioactive gas. You can’t see, smell, or taste radon, but it may be a problem in 

your home. 

•		 Radon is the second leading cause of lung cancer in the United States, with thousands of deaths each year. 

If you smoke and your home has high radon levels, your risk of lung cancer is especially high. 

•		 Radon comes from the natural breakdown of uranium and is released into the air you breathe. Radon is 

found all over the U.S. You and your family are most likely to be exposed to more radon at home, where you 

spend most of your time. 

EPA recommends that you or your landlord fix your home if radon levels are 4 picocuries per liter (pCi/L) or 

higher. Radon levels less than 4 pCi/L still pose a risk, and in many cases can be reduced. 

HOW TO FIND OUT IF YOU HAVE A RADON PROBLEM
 


You should test for radon. Testing is the only way to know if you and your family are at risk from radon exposure. 

Testing is inexpensive and easy, and millions of Americans have already tested their homes. EPA recommends 

testing all homes and schools for radon. 

KEY MESSAGES 

•		 Installing a radon system during 

rehabilitation or rebuilding can make 

installation easier and less expensive. 

•		 Fix your home if radon levels are 

4 pCi/L or higher. 

You can test your own home by using radon test kits available 

from home improvement stores and centers. Follow the 

directions on the packaging for “closing up” your home (see

below) and properly placing the device, and send it in after

the test to get your reading. You can also hire certified radon

professionals to conduct radon testing.

See http://www.epa.gov/radon/radontest.html

for information on finding certified radon professionals and 

your state requirements, if any. 

If you are doing a short-term radon test lasting just 2 or 3 days: 

•		 Close your windows and outside doors and keep them closed as much as possible during the test. 

•		 Heating and air conditioning system fans that re-circulate air may be operated, but keep the device away 

from vents. 

•		 Do not operate fans or other machines that bring in outside air. Fans that are part of a radon-reduction 

system or small exhaust fans operating only for short periods of time may run during the test. 

•		 Be sure to close your windows and outside doors at least 12 hours before beginning. 

•		 Do not conduct short-term tests during severe storms or with very high winds. 

In a post-disaster situation, damaged homes may not have the closed building conditions (windows, doors, 

roof, etc.) needed for testing. But installing a radon system during rehabilitation or rebuilding can make 

installation easier and less expensive. 

RE-ENTERING YOUR RESIDENCE AFTER ANY DISASTER
 


Re-entering your home after a natural disaster can pose risks to you and your family. If rescue personnel have 

searched your home, it may have a FEMA search marking. Here are some tips to make sure it is safe to re-enter 

the home: 

•		 Return home only when officials say it is safe. 

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•		 Do not allow children to participate in post-disaster cleanup work. 

•		 Check for structural safety including sagging ceilings or floors. 

•		 Check for loose power lines or gas leaks and make sure the electricity 

and gas are turned off. 

•		 Make sure floors are safe — water and mud make floors slippery. 

•		 People with breathing problems or who have weakened immune 

systems should stay away from the damaged residence. 

•		 If you find a trapped person, call 911. Do not attempt a rescue, as you 

may become a victim. 

•		 Be aware of health and sanitation hazards: 

o	 Avoid contaminated buildings and contaminated water as much as possible. 

o	 Wash your hands thoroughly with soap and clean water often when working with debris. 

o	 Wear proper clothing and respiratory protection. 

•		 Inform local authorities about health and safety issues, including chemical spills, downed power lines, 

washed out roads and dead animals. 

WHAT YOU CAN DO ABOUT RADON 

You with the help of a radon professional can fix a radon problem. Radon systems are very effective and 

durable. The cost of reducing radon in your home depends on how your home was built and the extent of the 

radon problem. Most homes can be fixed for about the same cost as other common home repairs. If your home 

wasn’t damaged too badly, test for radon. 

If you are rebuiding your damaged home or building a new home, you should build in radon-resistant features. 

When installed properly and completely, these simple and inexpensive features can reduce radon levels. In 

addition, installing them at the time of construction makes it easier and less expensive. These features include 

(see http://www.epa.gov/radon001/rrnc/): 

•		 If your house is on a poorly ventilated crawl space, installing a crawl space exhaust fan. 

•		 If your house is on a slab foundation and has high radon levels, installing a low-cost “subslab 

depressurization system.” 

•		 If your house is being built or rebuilt on a new slab foundation, using a 4-inch layer of clean, coarse gravel 

below the “slab,” or foundation (alternatives such as a perforated pipe or a collection mat, are appropriate); 

•		 Placing heavy duty plastic sheeting (6 mil polyethylene) as a vapor barrier on top of the gravel to reduce the 

amount of soil gases entering the house; 

•		 Running a 3-inch (or 4-inch for large homes) vent pipe, like the ones commonly used for plumbing, 

vertically from the gravel layer (stubbed up when the slab is poured) through the house’s conditioned space 

and roof to safely vent radon outside and above the house, installing stud shoes to reinforce any studs 

notched in construction, and labeling the pipe “Radon System;” 

•		 Sealing and caulking all openings, cracks, and crevices in the concrete foundation floor (including the slab 

perimeter crack) and walls with polyurethane caulk; and 

•		 Installing an electrical junction box (outlet) in the attic for a vent fan, which may be needed now or later. 

Reducing radon levels requires special knowledge and skills. You should contract with a qualified radon 

professional who is trained to fix radon problems and can help you pick the right treatment method. 

HOMEOWNER’S AND RENTER’S GUIDE TO REDUCING RADON AFTER DISASTERS

Check with your state radon office for qualified or state-certified radon professional contractors in your area 

(see http://www.epa.gov/radon/whereyoulive.html). You can also contact radon certification programs for 

lists of certified radon professionals in your area (see http://www.epa.gov/radon/rnlinks.html for links to the 

National Radon 

3 
Proficiency Program and the National Radon 

Safety Board), and see http://www.aarst.org 

for radon guidance from the American 

Association of Radon Scientists and 

Technologists. Selecting a professional to fix 

your radon problem is much like choosing a 

contractor for other home repairs — you may 

want to get references and more than one 

estimate. 

If you are considering fixing your home’s radon 

problem yourself, you should contact your state 

radon office for guidance and assistance. 

SAFETY TIPS ON USING PORTABLE GENERATORS 

If you use a portable generator for electricity, use CAUTION to avoid carbon monoxide poisoning and fires. 

•		 Use portable generators OUTSIDE and far away from buildings. 

•		 Do not put portable generators on balconies or near doors, vents, or windows. 

•		 Do not use portable generators near where you or your children are sleeping. 

•		 Never refuel a generator while it is hot. 

•		 See the OSHA website for generator safety information: http://www.osha.gov/OshDoc/ 

data_Hurricane_Facts/portable_generator_safety.pdf 

CLEARANCE BEFORE REOCCUPYING YOUR HOME 

Every new or rebuilt home should be tested after occupancy, even if it was built to be radon-resistant, to 

determine if the radon levels are below the EPA’s action level of 4 pCi/L. Testing should be conducted after the 

house has been closed up. If radon levels still exceed 4 pCi/L, the radon system should be activated by installing 

and operating a vent fan, if it doesn’t already have one. 

Today, many homes are built to prevent radon from entering. Building codes in your state or local area may 

require radon-resistant construction features. If you are buying or renting a new home, ask the owner or builder 

if it has radon-resistant features. The EPA recommends building new homes with radon-resistant features 

in high radon potential (“Zone 1”) areas. The EPA Map of Radon Zones is available at http://www.epa.gov/ 

radon/zonemap.html. 

LOCAL CONTACT INFO:
 


HOMEOWNER’S AND RENTER’S GUIDE TO REDUCING RADON AFTER DISASTERS, JUNE 2015 

Hurricane Sandy Rebuilding Task Force - Indoor Environmental Pollutants Work Group 

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