nationl property inspections radon power point
TRANSCRIPT
Inspections You Can Trust
Radon Environmental Issues for Real Estate Professionals
• No. 1 cause of lung cancer among nonsmokers
• Second leading cause of lung cancer in the United States and Canada (next to cigarette smoke)
• A smoker who is also exposed to radon has a much higher risk of developing lung cancer
• Claims 21,000 lives each year
What Is Radon?
• A radioactive gas
• Comes from the natural decay of uranium found in nearly all soils
• Typically moves up through the soil to the air of your home through cracks and other holes in the foundation
About Radon
• Any home may have a radon problem
• Radon can be found in any type of home, including new homes, old homes, well-sealed and drafty homes
• Radon can be found in homes with basements, crawlspaces or slabs
Where Radon Comes From
• Cracks in solid floors
• Construction joints
• Cracks in walls
• Gaps in suspended floors
• Gaps around service pipes
• Cavities inside walls
• The water supply
Where Radon Comes From
• Test for radon during a real estate transaction
• Fix the home if the radon level is 4 picoCuries per liter (pCi/L) or higher
• Radon levels less than 4 pCi/L still pose a risk, and in many cases may be reduced
Radon
Source: Zone and legend map provided by EPA Web site
• Even if built to be radon-resistant, every new home should be tested for radon as soon as possible after occupancy.
• If you have a test result of 4 pCi/L or more, a radon fan can easily be added to a passive system to make it an active system and further reduce radon levels.
About Radon
Ensure that the test is approved
o EPA does not approve radon test devices
o The National Environmental Health Association (NEHA) approves radon test devices
o The National Radon Safety Board (NRSB) approves radon test devices
Radon Testing
• Passive Devices o Charcoal canisterso Alpha-track detectorso Charcoal liquid scintillation
• Available in hardware stores (plumbing department)
• Generally requires at least 48 hours to complete
Testing Options: Passive Devices
• E-perm results can be calculated immediately upon retrieval of canister following the test period
• E-perm uses electret ion chamber (EIC) technology
Radon Canisters
• Active devices are the following:o Continuous radon monitors (CRMs)o Continuous working-level monitors
• Require operation by trained testers• Provide a continuous report of radon levels present • Reveal unusual/abnormal swings in the levels during the
test period• Designed to deter and detect test interference/tampering • More costly than a passive device • Ensure a more reliable result
Testing Options: Active Devices
• Instant results are available at the push of a button following the test period
Continuous Monitors
A method using an active or inactive system to reduce radon levels in a home
Radon Mitigation
• Gas-permeable layer (stone)
• Vapor barrier (prevents soil gas entry)
• Sealed joints
• 3- or 4-inch PVC pipe
• Junction box for future fan in attic
Passive Mitigation
Active systems use a fan to direct the radon out of the home:
• Sub-slab suction• Drain tile suction• Sub-membrane suction• Combination
Active Mitigation
• Sometimes there is a lack of drain tile for sub-slab homes to tap into.
• In most modern construction, there is a drain tile under the slab that, when tapped into, can achieve good communication.
• The pipe is run up through the attic and through the roof or side wall (interior), or on the exterior of the home.
Sub-slab Mitigation
Sub-slab Mitigation
All breaches need to be sealed (bathtub plumbing)
Suction point in furnace closet in center of home
• Installing a pipe through the slab to get to the drain tile can create good communication under the slab
• Sump pits need to be sealed to prevent the home’s conditioned air from being sucked out of the home
• Sump pits are also a good suction point to reach the drain tile
Drain Tile Mitigation
Sub-slab Mitigation
Suction point through slabSealed pump with clear cover
Drain Tile Mitigation
Suction point from sealed sump pit
• Homes with crawl spaces with high radon levels require a 6-mm vapor barrier to be installed on the floor and sealed to the perimeter wall
• All penetrations must be sealed through vapor barrier • A pipe is installed under the membrane and is the
suction point
Sub-membrane Mitigation
• Suction points from basement and crawl spaces and/or slabs can be joined together to run to the outside
Combination
• The pipe should terminate above the roof edge and not halfway up the side of the home to prevent concentrated radon levels from re-entrainment/re-entry back into the home
• SHOULD NOT use gutter/downspout as exhaust pipe
Pipe Termination
• SHOULD be above the eave of the roof
• SHOULD be 10 feet or more above ground level
• SHOULD be 10 feet or more from any window, door or other opening into conditioned spaces of the structure that are less than 2 feet below the exhaust point
• SHOULD be 10 feet or more from any opening into an adjacent building
Pipe Termination
Pipe Termination
Incorrect — too short Incorrect — gutterCorrect
• SHOULD be located on the outside of the home
• SHOULD be located in an attic
• SHOULD NOT be located in a basement or crawlspace
• Electrical disconnect SHOULD be located where fan is and not in another room
Fan Location
Fan Location
Correct — located outdoorsIncorrect — located in basement
Fan Location
Correct — located in attic
• Floor drains need sealingo Using a check valve, these floor drains can still
be used
• Fire collars are needed when a penetration occurs on the firewall, typically between the garage and the basement or crawl space
Special Items
Special Items
Special Items
