We finially have the Forum up for the Solid Surface Alliance. Unregistered guests can browse all but one of the catagories, but if you want to ask a question or comment, you need to register. Registeration is easy, fill out the usual form, the system will email you with a link to activate your account, then just log in as usual.
The forum is brand new, so there won’t be much content until the membership grows, so add a question or comment if you visit to help get the conversations going. New forums are tough to start, people look around, see little going on, and leave. But, with the volumne of questions we get from the public, this forum will save lots of time and make the answers available for all interested internet viewers to find.
There is one section off limits to all but invited members, that is the Scientific Section which is dedicated for those who are working on the issues. There they can spreak freely, bounce ideas off each other, and not worry about info getting picked up and repeated elsewhere before the proper time.
Please contact us if you have any problems signing up or logging on. Remember you MUST click on the link in the email that is sent to you to activate your account. You might have to scroll down one page when you open the email to find the activation link.
One of the many heavy metal radioactive elements that Radon decays into is Polonium 210, one of four Polonium stages that Uranium goes through as it decays. It has been known for more than 40 years that tobacco smoke contains the radioactive substance polonium-210 (PO-210), publicity surrounding the poisoning of former KGB agent Alexander V. Litvinenko with PO-210 in 2006 has heightened awareness of its presence in tobacco smoke.
Here is a link to a very well documented article on Polonium’s links to tobacco smoke. Lower levels will be found in homes with granite, but the radioactive element will be present and present not only a radiation hazard, but a chemical hazard from poisoning.
This news anchor has the news brought too close to home in this interview.
Dr. Subash Rashat of Hera Tech inc, Cherry Hill, NJ, talks about the heath effects of Radon from granite countertops. Dr. Rashat is an environmental Toxicologist. His English could use some work, but his answers are firm and unequivocal.
Three of my favorite quotes from this video.
“So we should have our granite tested for Radon and if we find it we should get rid of it?”
“Why are they using granite at all if in fact it is dangerous to our health?”
Great segment on the issues, with a Phd in Environmental Toxicology setting the record straight.
This Italian study lays out the issues of Radon and Thoron based radiation issues clearly. They lay out the strict correlation between Radon/Thoron and health risks while admiting that sometimes building material based Radon or Thoron are the most likely cause of high levels in a home.
Their materials in the study come from the Lazio region of Italy. Mostly igneous rocks, lava based, although they include some travertines. They point out that as much as 30% loss of result from leakage and back diffusion of the Radon. Back diffusion is where the Radon returns to the material instead of accumulating where it can be measured.
Another point is that moisture content actually raises the Radon release, the water inside the pores stops the Radon atom from recoiling into another crystal matrix inside the stone, stopping the Radon inside the pores and crevices where it can find its way out of the stone. Looking at Table 2, you can see the huge diference in Radon versus Thoron emitted in some stones, yet many of the Radon tests specifically omit any Thoron results as irrelevant. As much as 750 times more Thoron as Radon emitted.
The study has five conclusions, that building materials need to be classified by their Radon/Thoron exhalation rates, that leakage and back diffusion must be accounted for since it can reduce the measured levels by up to 30%, that the exhalation rates are dependent on grain size, humidity and temprature, that Thoron gas is a serious health concern and should not be dismissed, and that there should be catalogs of materials with Radon and Thoron exhalation rates so that builders could choose low level materials.
Indoor Air Quality: Information for the Builder and the Home Owner
By Dave Gerard & Paula Martin
Poor indoor air quality can harm your health, where the air you breathe can make you sick or, at its worst, cause deadly harm. We tend to spend much more time indoors during the colder seasons or during wet weather and, as a result, expose ourselves longer to a potentially harmful environment. Small children, with their higher breathing rate and their small lungs, have greater risk than adults. Even family pets can suffer from indoor air pollution. Luckily we know much more about indoor air pollution than we used to, about where it comes from and how to minimize its threat.
A large part of the problem of indoor air quality arises from the solution of another problem: expensive heating and cooling. Rising fuel and energy costs have forced the building industry to make homes more energy efficient, especially in the northern regions. Many of today’s homes benefit by default from improved building products and construction techniques that work toward eliminating the “leaky house” syndrome. Older homes are made more efficient by installing proper vapor barriers, replacing leaky doors and windows and by sealing cracks to the outside. When air infiltration is cut down, the building’s ability to breath (ventilate, or exchange air inside and out) is reduced, creating a risk for the “sick building syndrome”. A sick structure buildups stale air and odors, fumes, smoke, microbial by-products – pollutants remain in the air rather than get blown out with ventilation. The indoor air becomes intolerable or unhealthy.
Sources of indoor air pollution are both biological and chemical. Biological sources start from stale humid air. Moist conditions, created by plants, showers, fish tanks, cooking, poorly vented plumbing and even breathing may allow mold and mildew to grow. These microorganisms then release airborne spores and further microbial growth, causing problems ranging from dirty walls to allergic reactions, asthma attacks and respiratory infections. The dangers of black mold are known all too well to the building industry.
Chemical sources of indoor pollutants are many. Consumer products are often a culprit, including fragrant air fresheners, personal products and some household cleaning products (such as bleach). These irritants may responsible for persistent allergies and respiratory or sinus problems. Chronic conditions such as watery, burning eyes or skin irritations may also indicate unhealthy air in the home.
Combustion produces another indoor air pollutant. Homes that use gas appliances or have defective combustion heating devices can achieve high levels of dangerous exhaust gas in the home that pose immediate health dangers. Nausea, dizziness, headaches and even unconsciousness may result. All may be considered obvious signs of carbon monoxide poisoning, which is why many suggest having a carbon monoxide monitor in homes with gas appliances.
More dangerous chemical sources can arrive with home construction. The first of these is actually a category of chemicals, called volatile organic compounds or VOCs. These are often synthetic chemicals. They all share the characteristic that they evaporate (going from solid or liquid state to become a gas). VOCs are found in many of the products and construction materials used in the home. Particle board used in cabinets, counter substrate and furniture including upholstery, are all known to off-gas formaldehyde. Solvent-based finishes, oil-based paints, adhesives, paint strippers, carpets and some other flooring materials often emit high levels of VOCs. VOCs are health threats because they cause respiratory irritation, immune system problems, or, at their worst, cancer. Therefore many building material suppliers are creating products with “low VOC” ratings, to minimize risk.
Radon is another cancer-causing indoor pollutant. This pollutant has a natural origin. It is a tasteless, odorless, colorless and radioactive gas formed naturally from the decay of uranium and is most commonly found in soil, rock and water surrounding the home. Some areas in the U.S. are considered hot spots for radon gas while others have low risk, based on the region’s composition of underlying rock. Radon can seep into the home through cracks in concrete floors or other non protected penetrations and surfaces below grade or from off-gassing in the water supply during showers or other water usage. Radon has recently been discovered to be delivered to the home via some building products. Recently, unhealthy levels of radon have been detected in some natural stone products used in flooring, fireplace features and granite counter tops. Radon is a special risk because, as it undergoes radioactive decay, its breakdown products (called radon daughters) are also radioactive, but in solid form. Therefore, the radioactive gas may transform inside a home to a radioactive dust, making mitigation more difficult. The best way to deal with the threat of radon is to keep it outside your home.
People exposed to VOCs, radon gas (and its radioactive breakdown products) and other solvent-based fumes can damage the DNA in sensitive lung tissue, causing lung cancer and other serious health problems. The EPA estimates that indoor exposure to radon causes 8% of the cases of lung cancer in the US (cigarette smoking is responsible for 80%). If you or any of the occupants in your home experience symptoms associated with questionable air quality, consult an air quality specialist and have the air in and around the home tested, include testing the water if you use a private well. While many of the sources described may be obvious, VOCs and radon gas are hard to detect and require special testing equipment. If you determine you have an air quality issue, remediate the condition by first restricting or removing the pollutants at the source and increase or introduce ventilation.
According to ASHRAE (American Society of Heating, Refrigeration and Air-conditioning Engineers), the rate of air exchange is based upon square footage and number of occupants or bedrooms in the building. Based on a mechanical ventilation design, an average house of 1500-3000 sq ft with 4-5 bedrooms requires a continuous ventilation rate of 75 cubic ft per minute (cpm). If venting intermittently, the ventilation rate increases substantially. ASHRE standards have been amended for northern regions, requiring increased ventilation rates due to longer home occupation during the winter months. Protection from indoor air pollution requires appropriate air flow.
Natural ventilation methods, also know as “farm house or stacked venting,” simply employ opening doors and windows to create a “chimney effect”. While this may clear the air, it does not distribute fresh air uniformly throughout the building, plus, it wastes energy. That “fresh spring” smell of natural venting also invites unwanted spores, pollen, dust, insects and humidity to enter and be dispersed, possibly adding to the air quality problem.
Spot ventilation is achieved installing and operating fan units at know sources, directing the affected air to the outdoors via ducts. Range hoods, bath fans, and clothes dryers are all considered spot ventilators. This type of ventilation will depressurize the house and could result in air infiltration through cracks and leaks and cause combustion devices to back draft if make up air is not supplied. Clothes dryers should always be ducted to the outdoors, they product excessive amounts of moisture, lint and exhaust fumes if gas operated. Radon mitigation often involves creating a pressure differential between the exterior foundation, pulling the underground gas and venting it to the exterior air (rather than allowing it to be pulled into the interior of the structure), which helps only if the radon source is the rock upon which the house sits.
The most energy efficient and balanced systems used today are Heat Recovery Ventilators (HRV) and the whole house method. HRVs work as air-to-air heat exchangers designed to expel stale, warm air to the outdoors through an insulated duct while pulling in fresh air in a parallel duct at the unit. Because the inflow and outflows ducts are parallel, heat is partially transferred from the exiting air to the entering air, saving energy. With equal amounts of air entering and leaving, balance is achieved therefore eliminating depressurization and associated problems. Exhaust ducts are located at all pollutant sources and each living space fitted with fresh air diffusers. Whole house ventilation is an important consideration for the new home builder as it is the method by which energy can be conserved yet minimizes risk of indoor air pollution. With new construction, the builder has the opportunity to hide HRV duct work before covering up walls and ceilings. HRV control systems can be set up to run automatically. Their ventilation rate can be increased if excessive humidity, solvent based vapors and other fumes are present, and each exhaust intake location can be manually activated and run on a timer.
Builders and home owners have a greater range of choices today. With proper ventilation, the home owner can flip a switch to increase air flow and decrease health risk, especially while new furniture and carpets off-gas. Home owners can choose materials in their home (from cleaners to flooring) that release fewer fumes. Smart home buyers will consider not just the energy-star rating of their home but also its ventilation structure, to make sure they don’t buy either a leaky house or a sick one.
About the authors.
David Gerard is an expert in the building of super insulated homes and cold weather construction techniques, building in Alaska for the last 26 years. David also fabricates cabinets and countertops for his projects and is familiar with out gassing of materials.
Paula Martin is a (credintials will be added later)
A few weeks ago, the MIA, Marble Institute of America, broke a 14 year old position that said granite countertops contained no Radon or radioactivity. An unpublished study was used, claiming that of 13 stones tested, only one had very high levels 292 pCi/L. Their calculation was predictably low, as the MIA set the protocol for the test. 26 square feet of Crema Bordeaux, the 292 pCi/L level granite in the test, was shown to add .27 pCi/L to a 2,000 square foot home.
Three main organizations have set dose/risk factors for Radon, the ICRP, the EPA, and BEIR IV. The factors range between .2 and 1.2 extra cancers from a lifetime exposure to 1 pCi/L.
If the MIA study is taken at face value, that would mean between .05% risk and .32% risk of developing cancer from 26 square feet of Crema Bordeaux. But there is a problem with the MIA study, the amount of granite was too low for a home of that size.
The average countertop sold in the US is between 65 and 75 square feet, versus 26 square feet from the MIA study. So a more realistic square footage would be from 2.5 to 2.9 times more granite. One should take the .27 pCi/L found in Crema Bordeaux and call it between .675 and .78 pCi/L which would cause between 1.35% and 3.48% increased risk of cancer.
That is a significant difference.
Another problem with their study was the highest level granite is actually a pretty low emitter. Crema Bordeaux usually measures around .24 mR/hr (Alpha, Beta, and Gamma) for a area like that used in the MIA study, they show a picture of the Crema Bordeaux section tested in the study.
So, .24 mR/hr put out .27 pCi/L of Radon in a home? But some Crema Bordeax will run as high as 1.45 mR/hr, or 1.63 pCi/L using their ratio of radon to radiation. But use a reasonable amount of granite in that home, say 65 square feet, and now the Radon level is That level of Radon will cause from 4 pCi/L to 4.7 pCi/L in that example. Radon at that level has dose/risks factors between .9% and 5 %.
Here is an excellent white paper on Radon risks, recently updated. Note that over 20 Radon studies are currently in progress, they take time to track the people exposed and wait for them to develop health problems.
Another paper by one of the same authors above mentions that sealing aluminum foil or a dense coat of enamel paint helps the Radon gas decay in place, which has the effect of increasing Gamma radiation in the home.