Because radon reduction work is so new, most contractors will not guarantee a reduction in radon levels. Effectively blocking a major entry point, however, should result in some reductions of the overall radon level in you house. The result is likely to overload the footing drain or even if it doesn’t do so right away, eventually the footing drain clogs and the roof drainage ends up in the building basement or crawl space. However you may need to locate it several feet away as in the case of basement waterproofing. Radon from the soil-which enters the wall through joints or tiny pores and cracks-can travel through these connected spaces and enter the basement through similar openings on the interior side or through the openings in the top row of block. Diagnostic methods are mentioned here only as supplemental information to assist homeowners when working with radon diagnosticians and mitigators. Those homeowners who are confident they have the tools, equipment, and skills to do the job themselves may want to read EPA’s more detailed manual, Radon Reduction Techniques for Detached Houses: Technical Guidance (EPA/625/5-86/019). At this time, EPA does not endorse the use of air cleaners as a method of reducing radon decay products in indoor air because this technology has not been demonstrated to be effective in reducing the health risks associated with radon.
Air cleaners are commonly used to condition indoor air for a variety of health and comfort reasons, and there have been attempts to market air cleaners to reduce radon decay products. If you are planning to build a new home and are concerned about the potential for elevated indoor radon levels, you should consider measures to prevent radon entry into the house. A few contractors may be willing to guarantee a radon concentration of less than 4 pCi/L (picocuries per liter); however, for a contractor to make this promise he should first thoroughly evaluate the potential for radon reduction methods to work in your home. Although air cleaners will remove some of the radon decay products, many questions remain concerning the relative health effects of the decay products that are not removed and the potential impacts of the undiminished source of radon decay products. Since the radon health hazard is associated with the products of radon decay (which are chemically active), and not the radon itself (which is an inert gas), it is appropriate to ask whether it is feasible to remove the radon decay products without removing the radon gas itself. Until more is known, EPA believes that the available data do not warrant discontinuing the use of air cleaners already installed, nor can we suggest installing air cleaners to reduce your risk of exposure to radon and its decay products.
Definition of these factors is possible through a series of diagnostic observations and measurements made before, during, and after radon reduction systems are installed. The radon reduction methods discussed in this booklet concentrate on methods of removing radon gas or preventing radon gas from even entering the house. Once an action (or combination of actions) has been performed, it is important that you have further testing done to determine the level to which radon has been reduced. Use line marker spray or a string stretched between two small battens in the ground to mark the route you have chosen for your trench. In some areas, especially in the northeast and west, water from private wells or small community water systems can contain sufficient radon to contribute significantly to elevated levels within a house. The potential concern with radon in water is the airborne radon released when water is used. Eventually, this water seeps through and enters your home.
A recent EPA document, Radon Reduction in New Construction: An Interim Guide (OPA-87-009), is available to assist home builders and others interested in potential radon prevention alternatives in new construction. The measurement of radon levels in well water is a good way to learn whether water is an important contributor to the airborne radon level. Improperly designed drainage systems can do more harm than good. The GAC method has been more widely tested and is more commonly used in individual homes. The second uses granular activated carbon (GAC) to remove radon from the water. The effectiveness of any one method will depend upon the unique characteristics of each house, the level of radon, the routes of radon entry, and how thoroughly a job is done. The selection of appropriate and cost-effective radon reduction techniques for a specific house depends on how well the source of the indoor radon problem is understood, how house characteristics affect radon entry rates, and how candidate radon reduction systems influence the radon entry process. For more detailed information on radon in water wee the recent EPA booklet, Removal of Radon From Household Water (OPA-87-011).
Pouring a new slab would cost considerably more in a large unpaved area. Some of the methods are simple, some are complex, and some are much more expensive than others. Furthermore, holes that point up are perfect targets to get clogged with the rounded gravel. It can be frustrating to have to go through government channels to do work on your own yard, but you must remain patient and polite if you want to get this project done. You should be certain to get a written estimate of costs which stipulates the work to be done. No one can guarantee that these methods will work as they did in the test houses. The suggestions contained in this guide represent current knowledge and experience gained primarily from radon reduction tests and demonstrations on existing houses. In houses with marginal radon problems, covering exposed earth, along with sealing cracks and openings, may be a sufficient remedy. Water from large community water supplies releases most of its radon before it reaches individual houses.