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| Radon Gas & Microwave Leakage |
| Honest Home Inspections will gladly test for Radon gas in your home, see the "Fees and Service" page for details. Microwave Leakage detection is included in any inspection where the microwave is part of the sale of the property. The following information will try to answer questions you have in regards to radioactive Radon Gas and Microwave radiation. Please visit the links page on our website that will direct you to a government website provided by the EPA for Radon Gas. Some of the information below was taken from the government radon site. This site is a wealth of trustable information to help you make an informed decision. Unfortunatley for us, Wisconsin is an area known for Radon intrusion into our homes. |
What is Radon? |
Radon is a gaseous radioactive element having the symbol Rn, the atomic number 86, an atomic weight of 222, a melting point of -71ºC, a boiling point of -62ºC, and (depending on the source, there are between 20 and 25 isotopes of radon - 20 cited in the chemical summary, 25 listed in the table of isotopes); it is an extremely toxic, colorless gas; it can be condensed to a transparent liquid and to an opaque, glowing solid; it is derived from the radioactive decay of radium and is used in cancer treatment, as a tracer in leak detection, and in radiography. (From the word radium, the substance from which it is derived.) Sources: Condensed Chemical Dictionary, and Handbook of Chemistry and Physics, 69th ed., CRC Press, Boca Raton, FL, 1988
Sources of Radon are the Earth and rock beneath the home, well water, and some building materials.
OK, now that we have satisfied all of you science geeks let's try an easier explanation:
Radon is a colorless, odorless soil gas that comes from the natural disintegration of radioactive heavy metals uranium and thorium below the earths surface. Radioactive decay actually makes life on Earth possible by heating its core. |
How does it get into our homes? |
The air pressure inside homes is slightly lower than in the ground (typically 0.7-1.4 psi vacuum), which draws in radon gas from several feet away. Combustion appliances, like furnaces, water heaters, and fireplaces, as well as exhaust fans and vents, reduce the indoor air pressure. The warm air inside our homes naturally rises reducing the air pressure on lower floors. Strong winds can even create a vacuum. When the ground is frozen or soaked by rain, "bottled up" radon gas in the ground moves to the warm porous gravel and disturbed ground around the house, then up into the house.
The majority of homes, whether a slab or a basement, are built on concrete. Although extremely hard, concrete is actually porous. The naturally rising Radon gas is pulled into the house by the negative vacuum and in through openings or cracks and through the pores in concrete. Modern houses tend to build up radon, because the building envelope is almost airtight while the foundation is "leaky" to soil gas. The soil gas infiltration ranges from less than 1% to over 20% of the total "fresh air" infiltration into homes.
The heavy radon gas will usually accumulate in basements and on lower floors. Heating and air-conditioning, natural air movement, and diffusion of radon atoms through the floors and walls distribute radon throughout the house. |
What is Safe? |
Before we can answer the question "What is safe?" we must know how Radon is measured. Let's begin by asking the question: What are "picoCuries"(pronounced pi”ko-ku´re)?
The concentration of radon gas is not measured directly but rather by the radioactivity it produces. This radioactivity is expressed in picoCuries per liter of air, or "pCi/L". A Curie is a unit of radioactivity equivalent to 1 gram of radium and the prefix "pico" means a trillionth. In an average basement, 38 million atoms will undergo radioactive decay each hour.
SO, WHAT IS SAFE? PER THE EPA: "There is No Safe Radon Level!"
The U.S. Congress studied the risk to public health and set the "target" radon level for homes (The "Radon Act")as an outdoor level. Then, considering the high cost of fan radon mitigation, the US EPA issued more relaxed guidelines for homeowners:
Radon Guidelines for Homeowners
0.4 pCi/L is the "target" level for homes (The U.S. Congress)
2 pCi/L EPA's "consider action" limit - consider fixing your home!
4 pCi/L EPA's "action" limit - fix your home!
It is difficult for people to accept that their home, a place that one looks to for security, is hiding invisible danger. Yet, the average person receives a higher radiation dose from radon at home than from all other natural or man-made sources combined.
Outdoor radon levels in the U.S. range from 0.02 to 0.75 pCi/L (picoCuries per liter), averaging 0.4 pCi/L. But homes draw concentrated radon gas from the ground. Because radon is nine times heavier than air, elevated radon levels generally build up in basements and on lower floors. Although the U.S. Congress has set the natural radon concentration outdoors as the target level for homes, approximately two thirds of homes exceed it. A half of American homes have a radon level above 0.67 pCi/L (the median level). The average (mean) radon level in US homes is 1.25 pCi/L, or three times higher than the average level outdoors.
Nearly 8 million US homes, or 1 out of every 15, have radon levels above the EPA's 4 pCi/L "action" limit and nearly 1 out of 6 exceed the EPA's 2 pCi/L "consider action" limit. You should always try to reduce radon to a practical minimum - if you just settle for 4 pCi/L, your home will be more radioactive than 94% of US homes. The cancer risk is proportional to the radon level. Always reduce your radon level to a practical minimum! Reducing radon from your current level by 50% (or 80%) lowers the cancer risk to each member of your family by 50% (or 80%). |
Health Effects |
| Radon is the number one cause of lung cancer among non smokers |
| Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates. Overall, radon is the second leading cause of lung cancer. Radon is responsible for about 21,000 lung cancer deaths every year. About 2,900 of these deaths occur among people who have never smoked. On January 13, 2005, Dr. Richard H. Carmona, the U.S. Surgeon General, issued a national health advisory on radon. Visit www.cheec.uiowa.edu/misc/radon.html for more on a study by Dr. William Field on radon-related lung cancer in women and http://www.surgeongeneral.gov/pressreleases/sg01132005.html to read a press release by the surgeon General. |
How does Honest Home Inspections test for Radon in my home?
Honest Home Inspections is pleased to announce that we use Sun Nuclear digital radon testing machines to test for Radon. The NEW model 1028 continuous radon monitor is a patented electronic detection device used for the measurement of radon gas. The new model 1028 is intelligently designed to be fully programmable by the inspector. 
For accurate radon test readings, it is necessary that the house be closed up (windows and doors) for 12 hours before the inspection and 48 hours during the inspection. These conditions are as follows:
• Keep windows closed.
• Doors should not be opened except for normal entrance and exit.
• Any system which would bring outside air into the house should not be operated
• Large volume air exhaust systems should not be operated.
Heating and air conditioning may be operated normally. And, it is acceptable practice to operate the clothes dryer, range hood, and bathroom fan during the period of testing.
The testing device is programmed to shut down after 48 hours of testing and results can be obtained immediately from the equipment. A report can be provided on site if the request is made prior to the inspection/test otherwise results can be emailed within hours of the test.
How do I get rid of the Radon in my home?
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To reduce the Radon levels in your home we use a term called "mitigation". There are several ways that radon can be reduced and many companies that offer them.
Two key ideas are to either use vacuum to redirect the gases above the roofline or to seal the floor thereby reducing the porosity in the concrete. Both would reduce the effects the but the best and most common radon mitigation technique is called either soil depressurization, or active subslab depressurization (ASD), or subslab suction (SSD). This is by far the most common type of radon reduction system installed today. Generally, a hole is drilled through the basement slab, a cavity is excavated beneath the slab, and 3" or 4" diameter PVC pipe is run up from the slab, out through the basement wall, where it connects to an exterior mounted exhaust fan. From the fan, an exhaust pipe runs up at least 10 feet above ground level, and 10 feet from any windows. |
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The EPA has mitigation standards on their website www.epa.gov/iaq/radon/pubs/mitstds.html
Unfortunately, each home, like people, is an individual and may be difficult to perform either method. If your levels are above what is considered acceptable, do some research in your area, the Internet is a great tool, and obtain several quotes from qualified contractors. As always we will be happy to answer any questions for you. Honest Home Inspections does not profess to know everything however, if we don't know the answer we will find out!! |
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Microwave Leakage |
Have you ever watched up close as your leftovers heated in a microwave oven? Has your child? How much body penetrating microwave radiation do you think you took in? Would you like to know before you do it again?
Microwave oven leakage is serious business. Every year millions of children, pregnant women, and people of all ages stand too close to an operating microwave oven, exposing themselves to dangerous levels of body penetrating microwave radiation. Microwave radiation is known to cause cataracts, birth defects, cancer and other serious health problems. Warning labels are included in every oven owner's manual. The FDA takes the problem so seriously, it has set legal limits on the amount of leakage permitted. |
Does your Microwave leak? |
| So you are about to buy your dream home with that great kitchen and a built in microwave above the stove. How convenient. But how old is that microwave and what kind of shape is it in? Microwaves have been around for decades. The real push began after 1975 and now 90% of US homes have a microwave oven. Therefore that microwave that looks fairly new could in fact be quite old. But age doesn’t really matter too much. Leakage does! |
What is Microwave Leakage? |
| Microwave leakage is a big enough concern that the FDA has established limits as to microwave leakage. There is little cause for concern about excess microwaves leaking from ovens unless the door hinges, latch, or seals are damaged, or if the oven was made before 1971. All microwave ovens made after October 1971 are covered by a radiation safety standard enforced by the FDA. The standard limits the amount of microwaves that can leak from an oven throughout its lifetime. The limit is 5 milliwatts of microwave radiation per square centimeter at approximately 2 inches from the oven surface. This is far below the level known to harm people. Furthermore, as you move away from an oven, the level of any leaking microwave radiation that might be reaching you decreases dramatically. For example, someone standing 20 inches from an oven would receive approximately one one-hundredth of the amount of microwaves received at 2 inches. |
How does leakage occur? |
| Leakage will normally occur through the microwave door. Microwave leakage is a big enough concern that, as mentioned before, the FDA has established limits as to microwave leakage. Be wary of any that appear to have a damaged door, seal or hinges. Since the door is really where leakage occurs most of the time it is dependent on the use and care the microwave has seen over the years. Many of the microwaves permanently mounted above the stove are absorbing a great deal of heat and contaminants from the stove itself. The door seal is our concern and many times all it takes is just a good cleaning (see Tips on Safe Operation below). Others need to have the seal replaced or at times it may be worth replacing the unit. |
How is the radiation measured outside the microwave? |
| Microwave radiation is measured as power density in units of milliwatts per square centimetre (mW/cm²) which is essentially the rate of energy flow per unit area. One needs special equipment for the detection and measurement of the leakage. Typical levels of radiation leakage from microwave ovens is about 0.2 mW/cm² which is far below the limit set by the national safety standard Safety Code 6: Limits of Exposure to Radiofrequency Fields at Frequencies from 10 kHz-300 Ghz (1994, 60 p., Health Canada pub. 91-EHD-160) and the FDA. This level of leakage cannot be sensed by the body. |
How does Honest Home Inspections test the Microwave for leakage? |
| We are using a digital microwave oven leakage detector. Measurements shall be made with the microwave oven operating at its maximum output and containing a load of 275±15 milliliters (1 cup) of tap water initially at 20°±5° Celsius 68°±5° Fahrenheit placed within the cavity at the center of the load-carrying surface provided by the manufacturer. The water container shall be a low form 600-milliliter beaker having an inside diameter of approximately 8.5 centimeters (3.34 inches) and made of an electrically nonconductive material such as glass or plastic. Measurements shall be made with the door fully closed as well as with the door fixed in any other position, which allows the oven to operate. The meter will be placed approximately 2” from the microwave door seal and measured across the entire seal length. Our meter is capable of a range from 0 - 9.9 mW/cm² (no more than 5 MW is recommended by the FDA). |
Tips on Safe Microwave Oven Operation |
* Follow the manufacturer's instruction manual
for recommended operating procedures and safety precautions for your oven model.
* Don't operate an oven if the door does not close firmly or is bent, warped, or otherwise damaged.
* Never operate an oven if you have reason to believe it will continue to operate with the door open.
*Some ovens should not be operated when empty. Refer to the instruction manual for your oven.
*Clean the oven cavity, the outer edge of the cavity, and the door with water and a mild detergent. A special microwave oven cleaner is not necessary. Do not use scouring pads, steel wool, or other abrasives.
*To add to the margin of safety already built into the oven, don't stand directly against an oven or peer inside of the oven (and don't allow children to do this) while it is operating.
*Users should not heat water or liquids in the microwave oven for excessive amounts of time a phenomenon of superheating can occur. Visit www.fda.gov/cdrh/consumer/microwave.html#11 for information on superheating. |
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