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You can fix a radon problem.

(Called: reduction, correction, mitigation, remediation, etc.)

SOIL SUCTION - FAN SYSTEMS (Sub-Slab Depressurization, etc.)

EXPECTED RESULTS...... Our experience in over 10,000 installations agrees with EPA studies. Reductions are typically 80-99% (often to about 1-2 pCi/l). Effectiveness is expected for as long as the system operates. Guarantee periods provide a reasonable time for assurance of quality and reliability.

TYPICAL SYSTEM DESIGNS:

New Construction
 A small fan controls soil air which contains radon. The fan draws air from under the home and exhausts to the outside where radon quickly dilutes.

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Costs to operate are extremely low and checking that the fan is running is about the only maintenance. Radon tests each two years are advised by EPA.

 
SEALING
(Sealing of primary cracks and openings to soil.)

EXPECTED RESULTS...... sealing alone is unpredictable and can never be guaranteed. (Sealing is usually required as part of Soil Suction - Fan Systems).

"EPA does not recommend the use of sealing alone to reduce radon because, by itself, sealing has not been shown to lower radon levels significantly or consistently."

..... "At risk expenses" are always wagered when sealing only (i.e. additional tests) and there is a limit to the practicality of sealing efforts. A substantial leakage area will still exist (invisible to the eye) regardless of meticulous efforts.

..... Sealing alone may sometimes reduce levels by about half if all openings and primary cracks are accessible to seal. However, little or no effect may be seen and levels can even go up. Chances are severely reduced by;

  • Initial radon levels above about 6-7 pCi/L.
  • Inaccessible items-areas which can't be sealed.
  • Meager efforts. (Poorly advised or... "a price too good to be true")

ACHIEVING ACTION LEVELS: 4.0, 2.7, 2.0


4.0 pCi/L
Achieving below the USEPA action level of 4.0 pCi/L can be accomplished for virtually any home. Older homes can present challenges due to construction practices when they were built and in special cases it can become a question of expense versus benefit.


2.7 pCi/L
The World Health Organization (WHO) has recently modified their recommended action level from about 5.3 pCi/L to about 2.7 pCi/L. This reflects recommendations regarding life-long, direct exposure. The change reflects recent population studies for statistical evidence of radon induced lung cancer.


2.0 pCi/L
The USEPA recommends to consider action between 2 and 4 pCi/L since no exposure is safe. However, around about 2.0 pCi/L and lower, the lower limits of sensitivity for test devices has been reached and errors up to 300% have been seen to occur. Hence, verifying less than 2.0 pCi/L is not truly feasible (though some contractors knowingly or unknowingly make such claims or warranties).


0.7 pCi/L
Outside air anywhere on earth. This is so low that even the best equipment scientists use can only estimate between 0.4 to 0.8 pCi/L.

EXPECTATIONS AFTER RADON SYSTEM INSTALLATION:

One can expect reductions to below 4 pCi/L. More often retests show close to outside air (or below 2.0 pCi/L) in the worst case basement areas. (Note however that readings around 2.0 or lower are below the range most devices are capable of for accurate measurement.) Radon Concentrations in areas above a basement where people may spend more time are often 1/3rd to 1/2 the basement concentrations.

Note, about one in fifteen systems need adjustment. Retest quickly after installation with a continuous monitor where hourly readings can help identify problems and verify success. Thereafter, home test kits may be recommended as an independent, inexpensive and effective method for continued verification.
 

NOTE: Information provided here is
intended to be simplistic in description.