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Asbestos is a mineral that has excellent binding qualities. It
is a long-lasting, dependable material that is not soluble in water
and has been used successfully in building products and components,
and insulations for many decades.
In the 1960’s concerns surfaced about asbestos and its relationship
to some cancers. Workers in some industries as well as miners were
developing cancers caused by asbestos in the air they were breathing.
These cancers affect the lungs and respiratory system. Public awareness
evolved from testing in public and commercial buildings, schools
and hospitals to testing in homes.
Once it was determined that asbestos could have a negative impact
on the health of people who are exposed, the production of asbestos
was banned for use as building materials, insulation, etc. Production
of asbestos ceased in 1973 and its installation was banned after
1978.
Typical uses and locations found in homes are:
- Insulation: Rockwood insulation is found mostly in attics and
sometimes in walls. Ovens, ranges, toasters, dishwashers, heating
pipes, ducts, boilers and furnaces would typically have insulations
which contain asbestos during the years from about 1910-1975.
- Building materials: Asbestos in cement siding and roofing were
very common in the 1940s and 1950s. Transite ductwork was used
below concrete floor slabs, as chimney flues and as 1/4"
thick sheets for fire protection. Vinyl: Asbestos floor tiles
wre the tiles of choice form 1930 to 1970. Ceiling tiles and some
spray-on textured or popcorn ceilings have ACMs. It is not likely
that you will find asbestos in a home that was built after 1978
The main concern with the ACM is its condition. If the material
is friable, which means the asbestos fibers can become airborne,
it should be mitigated. Mitigation occurs in two forms: removal
and encapsulation. Removal is almost always the preferred solution
becuase it is unknown how long the encapsulation will last and the
release of fibers will re-occur.
The presence and type of ACM can only be determined by analysis
under a microscope. It cannot be determined visually.
The mitigation process is very specific and the cost is not much
higher for removal than it is for encapsulation.
Removal requires the following;
- Prepare the area with positive airflow to the exterior to capture
and discharge airborne particles to the exterior. Small asbestos
particles can remain airborne for days in still air.
- Wet down the ACM as well as adjacent areas of concern, such
as the floor.
- Isolate the areas and the ACM. This is typically accomplished
by building a platic tent around part of of the subject area.
The tent is moved to isolate other areas with ACM as needed.
- A proper respirator should be worn to capture the smaller ACM
particles. Goggles and disposable coveralls should also be worn.
- Removed ACM is captured in bags, transported in trucks designed
for this use, and disposed of at designated hazardous waste locations.
- The mitigator removes coveralls and then showers in a plastic
tent in the mitigation area.
- Air testing is performed after removal and clean-ups to determine
if there are asbestos particles in the air.
The cost for removal is specific to the contractor. However, removal
in a residential situation can be accomplised for $500 to $2500.
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Greenpeace may be addressing environmental concerns around the
planet, but your home inspector addresses environmental concerns
in the home.
Radon
Radon is a naturally occurring radioactive gas formed by the decay
of uranium atoms that are naturally present in rock and soils. Since
uranium is a common element in rocks and soils throughout the United
States, radon is constantly being generated.
In outdoor air, radon is diluted to such low concentrations that
it is usually nothing to worry about. However, once inside an enclosed
space (such as a home), radon can accumulate.
Indoor levels depend both upon a building’s construction and
the concentration of radon in the underlying soil. In addition,
radon can sometimes enter a house through it’s water supply.
The only known health effect associated with elevated exposure
levels is an increased risk of developing lung cancer. Not everyone
exposed to elevated levels of radon will develop cancer, and the
time between exposure and the onset of the disease may be many years.
Your risk of developing lung cancer from exposure to radon depends
upon the concentration level and time of exposure. Exposure to a
slightly elevated level for a long time may present a greater risk
of developing lung cancer than exposure to a significantly elevated
level for a short time. In general, your risk increases as the level
of radon and the length of exposure increases.
Asbestos
There are three forms of asbestos typically found in homes or buildings:
(1) Sprayed or trowled on surfacing materials, (2) insulation on
pipes, boilers, and ducts, and (3) miscellaneous forms such as wallboards,
ceiling tiles, and floor tiles.
The main concern about exposure to asbestos is based on evidence
linking various respiratory diseases with occupational exposure
in the shipbuilding, mining, milling, and fabricating industries.
Friable (easily crumbled) asbestos-containing material (ACM) and
that material disturbed during maintenance, or repair and renovation
are of greatest concern from a safety perspective. In general, any
materials which are suspected of containing asbestos should be painted,
taped over, encapsulated, or removed.
Urea Formaldehyde Foam Insulation (UFFI)
UFFI was an insulation product manufactured at the job site by the
installer. It was typically installed from the early 1970’s
to about 1980.
Urea formaldehyde-based resin, a foaming agent, and compressed
gas are fed into equipment to produce a foam, similar to shaving
cream. In retro-fit applications, the foam is pumped through a hose
into the wall cavity where it cures and becomes firm.
During and after the installation of UFFI, a formaldehyde gas can
be released into the living quarters and inhaled by the occupants.
Inhaling formaldehyde vapors released from UFFI has caused some
people to experience symptoms such as eye, nose, and throat irritation,
persistent cough, respiratory distress, skin irritation, nausea,
headache and dizziness. Air sampling tests may show positive or
negative from day to day. The amount of toxic fumes are directly
related to the amount of humidity in the walls and changes with
the changes in the humidity (i.e., there are always more toxic traces
on the north side of the house. Also, the further north you go,
the more severe are the problems).
The formaldehyde off-gassing ceases after a few years. There is
almost no concern with this off- gassing anymore.
Other possible hazardous materials used in construction include
lead solar used in some copper pipes, lead water pipes, and PCB’s
contained in some fluorescent light fixtures.
We will focus on the newest environmental concern - lead paint
- in a future column.
For further information on Radon, Asbestos and UFFI, we recommend
contacting the Consumer Product Safety Commission in Washington,
DC at 1-800-638-2772.
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Have you ever wondered what might be lurking in the water you’re
drinking?
There are millions of different bacteria, chemicals, minerals and
toxins in the water we drink. However, they are at trace levels
and are, for the most part, tolerable.
Your best protection is to learn about your water and test it regularly.
Water labs will be able to give or direct you to a source that will
outline the acceptable parameters or tolerances of the compositions
or conditions that may be found in your tap water. A local lab should
also be a good source of information for the most common problems
found in your area.
Here is an overview of a few of the dangerous concerns found in
some water.
- Coliform bacteria. This is waste from animals or humans. This
situation can develop in areas where there are large populations
of humans or animals. Surface water may be washed into wells or
their underground aquifers. In older communities, cesspools were
much deeper in the ground and closer to water tables. New community
requirements put on-site water systems closer to the surfaces
and farther from the water tables. There is no acceptable coliform
bacteria level for water that is to be consumed.
- Nitrates. These chemicals may cause neurological problems.
- Pesticides. These are found in areas where foliage is sprayed
or dusted. Rain washes the pesticides to the surface and possibly
to wells or underground aquifers.
Proper balanced water is 7.0 PH. When the PH is below 7.0, the
water is acidic. With levels above 7.0, the water is alkaline, or
base. It is very common to see water with low or acidic PH, especially
in municipal water supplies or densely populated areas.
Low PH can be recognized at sinks and tubs after a few years by
the greenish stain at the drain. This stain is caused by the chemical
reaction of the acidic water and the copper piping. The acidic water
causes copper to be depleted from the pipes to the point of failure,
or leaking. Advanced stages of this activity can be evidenced by
small, round, green stains on the pipes. This is an indication that
the pipe is newspaper thin and will leak at any time.
Legal limits of acidic PH are typically 6.2 to 6.5, depending on
geographic location. The levels are measured on a logarithmic scale.
High levels of minerals will manifest themselves by leaving brownish
stains at the sink and tub drains and in the toilet tanks.
Here is a partial list of maximum contaminant levels (MCLs) set
by the U.S. Safe Drinking Water Act:
| Component |
Condition MCL |
| Total Coliform |
1.0 |
| PH |
8.5 |
| Nitrate |
10 |
| Manganese |
.05 |
| Magnesium |
.0 |
| Alkalinity |
.0 |
| Total Dissolved Solids |
500 |
| Sulfate |
250 |
| Hardness |
250 |
| Lead |
.050 |
| Nickel |
.0 |
| Copper |
1 |
| Potassium |
.0 |
| Sodium |
.0 |
| Iron |
.03 |
| Fluoride |
2.4 |
| Arsenic |
.05 |
| Cadmium |
.01 |
| Silver |
.05 |
| Chloride |
250 |
| Barium |
1 |
| Chromium |
.05 |
| Mercury |
.002 |
| Selemium |
.01 |
| Calcium |
0 |
There is treatment equipment on the market that will address these
issues and hundreds more. You should know what is in your water
and the possibility of problems before you call a treatment specialist.
The better informed you are, the higher the probability of purchasing
a system that will be best for you, if a system is needed at all.
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Water wells are somewhat mysterious because most of the well system
is in the ground and not visible.
Wells are dependent on water from underground water supplies or
"aquifers". We cannot know how much water is accessible
to the well or how fast the water will be replaced.
Some underground water moves at very slow rates due to the condition
of the soil or aquifer source. Water in the soil may be moving at
a slow rate of 4" an hour or as fast as 100 miles a day.
If the soil is dense, like clay, water will be moving at slower
rates. If the soil is sandy or the stone is a shale, water will
move quickly. A local well driller may be able to provide information
based on his experience drilling wells.
When the well driller reaches water, he continues to drill in an
effort to accumulate enough water to service the house on an ongoing
basis. The depth of the well is determined by the well driller and
will be much deeper than the depth at which water was found.
There must be water above and below the pump to keep it from drawing
up debris from the bottom or from drawing down form the top if there
was a high demand. The height of the water above the pump provides
a gravity assist, which helps the pump lift water up to the house.
The pressure to the house is not provided by the pump. The only
function of the pump is to lift water out of the well and deliver
it to the pressure/storage tank. You can get water to any fixture
whether the pump is on or not.
Pressure to the house is provided by the air pressure in the water
storage tank. When you open a faucet, the compressed air in the
tank is relieved by pushing water as you demand.
When the pressure in the tank gets to a point approximately two
to three pounds above the low pressure limit, the pump comes on
to deliver more water to the tank. However, it is the compressed
air in the tank, with additional compression from the introduction
of water, that provides the pressure.
The limit control is a relay that is an automatic switch and controls
the on and off action of the pump, based on the pressure in the
system.
What goes wrong with well systems?
Air loss in the pressure/storage tank is the most frequent problem
with well systems. It can affect water delivery as well as shorten
the life of the pump due to its frequent on/off cycling.
Wells may "draw down" because of high demand or low supply
from the underground aquifers. Low supply from the aquifers may
necessitate drilling the well deeper or drilling a new well.
Pumps have a typical life expectancy of approximately 20 years.
If they fail prematurely, it’s usually due to short cycling
systems. In most cases, the supply piping from the pump to the top
of the well will also need replacing. Control problems, foot valve
leaks, storage tank failures, deteriorated well casings, etc.,require
attention but to a somewhat lesser degree.
Testing the water quality is very important and relates to the
health of the occupants. Coliform bacteria has always been the most
significant concern because it is from fecal waste of animals or
humans.
Other concerns are PH level, nitrates, manganese, and, depending
on geographic location, there are numerous other concerns such as
volitile organic compounds (VOCs) and a myriad of other chemicals
and minerals.
Contact a local lab to help determine what problems are common
to the area. Shallow wells (not more than 25’ deep) and springs
are more vulnerable to surface contaminants such as fertilizers
and pesticides.
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Everything electrical, whether it’s a toaster or a major power
line, is surrounded by electric and magnetic fields (EMF). Because
the two fields are often present at the same time, they are referred
to jointly as electromagnetic fields.
Electric fields are present whenever an appliance is plugged in.
Magnetic fields exist only when an appliance is plugged in and turned
on. Electric fields in a building come mostly from wiring and appliances.
Both internal (e.g., appliances in operation) and external sources
(e.g., power lines) contribute to a home’s total magnetic field.
The higher an appliance’s wattage, the greater the strength
and extent of the field. The strength of EMF decreases with distance;
it drops dramatically two feet away from household appliances. You’d
have to move 200 feet away from a major power line before there
is a significant decline in the strength of the its EMF. Although
electric fields are weakened by trees, earth, and buildings, magnetic
fields are not affected.
Recent studies show that EMF exposure may cause biological effects
in cells and behavioral effects in laboratory animals and insects.
Large-scale laboratory studies are being conducted to determine
the long-term health effects of exposure to EMF. The U.S. Department
of Energy has recently established the National Electric and Magnetic
Fields Advisory Committee to design and carry out research and conduct
a public information dissemination program on EMF. However, the
U.S. Environmental Protection Agency (EPA) does not directly link
adverse health effects to exposure to "low-frequency"
EMF at this time.
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