The most common unit that radon is reported in is "pCi/L," which means the number of picocuries (pCi) per liter (L) of air.
This is a measure of the level of radioactivity per unit of volume of air, because a pCi is defined as one trillionth of a curie.
A concentration of one pCi/L is just the amount of radioactive gas existing in one liter of air having an activity of 2.22 disintegrations per minute, Snead said.
Much is known about typical radon concentrations in Kansas and the nation.
"The national average radon concentration in homes is 1.3 pCi/L," Snead said. "The typical measurement of radon in outdoor air is about 0.5 pCi/L or less, but there is always some radon present."
The Kansas Department of Health and Environment has been compiling radon measurements in a database since 1987. As of Jan. 1, 1996, there were 15,494 measurements in the database. Of these, 5,646, or 36 percent, were greater than the EPA's recommended maximum indoor average concentration of 4.0 pCi/L. The highest recorded measurement is 204.4 pCi/L, and the statewide average, which includes all measurements, is 4.3 pCi/L.
"What this means is that there is definitely the potential for elevated radon concentrations to be found in typical Kansas homes," Snead said. "The only way to know the level of radon in your home is to test."
Snead said home and business owners should call their county extension office to see if it has inexpensive test kits available for purchase and for more information."
Is it feasible to heat a swimming pool with solar energy?
"If your pool is outside in the sun, it's already being solar heated," said Gene Meyer, extension specialist in small business energy at Kansas State University. "But some type of supplemental heat will be necessary to keep the water at a comfortable 78 degrees in the ealry spring and late fall.
To use solar collectors to warm the water, you will need collector area equal to between 50 to 100 percent of the pool surface area. Most solar pool heating systems cost between $3,000 and $5,000 depending on the size of the pool and other site specific conditions.
"The collector area can be reduced if you use certain conservation strategies," Meyer said. Because a pool loses heat primarily from evaporation at the pool surface, a transparent cover floated on the water when the pool is not used will reduce heat loss. Even a fence to shelter the pool from the wind will help.
June 9, 1996
Is there any danger of my solar collector overheating during the summer months when I'm not using it?
Yes.
"If the collector is not adequately protected from sunlight, damage may result from overheating," said Doug Walter, extension specialist in residential energy at Kansas State University.
Home-built, wooden collectors are most vulnerable to damage from overheating because the wood can dry out and crack, causing air leakage. But even metal framed collectors can overheat, causing the absorber to warp or the glass to crack.
"Of course, if your collector is used to heat water during the summer, it should be left exposed to sunlight," Walter said.
The most effective way to protect a solar collector in the summer is to cover the glazing with a tarp or a shutter. This is especially important if the collector is mounted at an angle other than vertical.
Vertical collectors mounted on walls often can be shaded with an overhang or natural vegetation, as long as the vegetation doesn't shade the collector in the winter.
Some collectors have vents that can be opened in the summer to allow hot air to escape.
"Collectors that circulate water, however, cannot be vented and should be covered or shaded," Walter said.
In short, don't expose your solar collector to full sunlight during the summer unless the hot air is allowed to escape. Covering the collector provides the best all-around protection, Walter advised.
Should I extinguish the pilot light in my furnace during the summer months?
Yes, if you want to save energy.
"Although the volume of natural gas consumed by a pilot light in a furnace varies, it will burn approximately 700 cubic feet per month," said Bruce Snead, extension specialist in residential energy at Kansas State University.
This not only wastes energy directly when the pilot light is unneeded, but also adds a small amount of energy to the house which, in the cooling season, must be removed by the air conditioner.
Many gas supply companies have a minimum charge in their rate schedule.
"During the summer, most homes consume less than this minimum amount of natural gas," Snead said. "Therefore, extinguishing the pilot light may not result in a dollar savings on the utility bill, but you will save the energy."
When extinguishing the pilot, turn off the gas valve to the pilot and main valve to the furnace. Extinguishing a pilot light during the summer will not reduce the life of the furnace, as was once thought.
June 16, 1996
I would like to finish my basement walls by framing on the inside and installing insulation between the studs. Should the vapor barrier be installed on the inside of the framing, as is normally done in above grade construction, or against the concrete wall to prevent ground moisture from getting into the insulation?
"If you have a damp basement. it is probably wise not to insulate the walls," said Doug Walter, extension specialist in residential energy at Kansas State University.
Installing a vapor barrier against the concrete wall will protect the insulation for a while, but it will not stop moisture from coming through the wall. Most moisture problems in damp basements must be corrected on the outside of the basement wall through improved drainage or waterproofing.
"If the basement is dry, the vapor barrier should be installed on the interior of the framing after the insulation is in place," Walter said. "This will prevent moist air from coming in contact with the cold concrete wall where it can condense."
Is a heat pump in the cooling mode more efficient than an air conditioner?
Not always.
"The principle by which an air-source heat pump operates in the cooling mode is identical to that of an air conditioner," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
In theory, the efficiency of both devices under the same conditions should be the same. Additional mechanical requirements in a heat pump, however, may slightly lower its efficiency as a cooling device.
"This difference is not universal," Hayter said. "In fact, the reverse may be true, depending on the model and manufacturer."
June 23, 1996
How can I control the summer humidity in my home?
"Your first step is to minimize the sources that add water vapor to your home," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
In the summer, air leaking into the home from the outdoors brings moisture which must be removed through air conditioning or dehumidification.
Although weather-stripping and caulking will reduce the infiltration of outdoor air, you also should attempt to minimize the amount of vapor generated within the home. Be sure that your clothes dryer is vented properly and that you operate the exhaust fans in your bathroom during showering and over your range when cooking.
"Schedule family activities that contribute to the humidity level in the home during the evening so that you can open windows rather than run your air conditioner," Hayter said. "This includes dish washing and baking."
You can lower the relative humidity mechanically by operating either your air conditioner or dehumidifier. Both devices lower the temperature of the air passing through the unit to the point that the water vapor condenses on the cooling coils and drains to a floor drain or pan. Occasionally check the drain to make sure it has not been plugged.
"Unlike the air conditioner, the dehumidifier is totally enclosed within the home," Hayter said. "Therefore, the energy removed from the air during cooling, as well as the energy to the compressor, is returned back to the home in the form of heat."
For dehumidifiers to maintain satisfactory humidity levels, the entire volume of space to be dehumidified must move through the dehumidifier once an hour. This depends on the airflow rate and the location of the dehumidifier.
"The dehumidification capacity of most dehumidifiers sold in the United States is certified by the Association of Home Appliance Manufacturers (AHAM)," Hayter said. "The capacity of the unit will be stated in pints of moisture removed per 24-hour period."
When selecting a dehumidifier, your choices include, in addition to capacity, a manual on/off switch or a humidistat (an automatic humidity sensing controller), a switch to turn the unit off automatically if the receptacle holding the water removed is full unless it drains continuously, and an automatic defroster for controlling frost on the cooling coil.
June 30, 1996
I would like to install air conditioning in my home, but I don't have a forced air heating system to which air conditioning can be added. Are there any alternatives to window air conditioners?
Yes, two alternatives to window air conditioning are available to you: through-the-wall unitary air conditioners and nonducted, split system air conditioners.
"A unitary air conditioner simply means that all of the components are in a single cabinet, much like a conventional window air conditioner," said Doug Walter, extension specialist in residential energy at Kansas State University.
A through-the-wall unit, however, generally is wider and less deep than a window unit. Typically it is installed at floor level below a window.
One advantage of a through the wall unit is that it doesn't obstruct views, light and ventilation through the window.
"Winter weatherization of the unit also is much easier than window air conditioners, which must be removed and stored or covered and sealed," Walter said.
Two disadvantages are a noise level similar to that of window units and the need to cut a permanent opening through an exterior wall of the house.
Nonducted, split system air conditioners are relatively new to the residential market. They consist of two distinct components, a condensing unit and a fan coil; hence the term split system.
The condenser and compressor are located outside the house just like a central air conditioner, while the fan coil unit is located in the space to be cooled. Several mounting options are available, including wall-hung, ceiling hung and suspended ceiling mounting.
Some models allow two or three condensing units (the inside components) to be connected to a single compressor unit outside (actually, multiple compressors in a single cabinet).
"With this system, you must make a provision for draining the condensate to the outside or into the waste drainage system," Walter said.
Split systems offer the advantages of greater flexibility in location, greater range of capacities and less noise. Their cost is similar to central air conditioners, but without the additional cost of installing a ducted air distribution system.
Through-the-wall units and nonducted, split systems are also available as heat pumps, allowing them to provide both heating and cooling for a room.