Asbestos is a naturally
occurring substance, which was widely used because of
its ability to withstand high heat loads without burning
or breaking down. Unfortunately, it was discovered that
over time it breaks down into small fibers that when
ingested become lodged in the lungs where it builds up
and destroys the tissue and can cause serious health
problems including Mesothelioma which is a cancer of
the chest and abdominal membranes caused by the inhalation
of asbestos and Asbestosis, a chronic disease of the
lung which makes breathing progressively more difficult.
These diseases can lead to death but because it has a
latency period of twenty to forty years, it takes a while
for manifestation of the symptoms.
In 1971 asbestos was
listed as an EPA hazardous air pollutant, but because
its use in the past was widespread it is still possible
to find it in a variety of places in both residential
and commercial applications. Asbestos should only be
considered a problem if it is breaking down or falling
apart, allowing its' fibers to become airborne. Removal
or encapsulation (sealing the asbestos, normally beneath
a wrapping of epoxy) should only be conducted by a
licensed contractor trained to handle the remediation
of it. If asbestos is found and is in good condition,
care should be taken not to disturb it or damage it.
Below, is a list of common places where asbestos can
be found. If in doubt, a sample of the suspected material
can be collected by a professional testing company and
tested for its' content.
Hot Water and Steam Pipes
Between 1920 and 1972, asbestos was
pre-formed in half rounds then wet-gauzed in place around
pipes. Pipes were also wrapped in asbestos paper tape.
If a whitish material is around the pipes (usually in
the basement) it may be asbestos. Test, monitor and take
further steps as necessary.
Ducts and Furnaces
In the 1940's and 1950's ducts and furnaces
were insulated with asbestos impregnated papers. Chalk
colored insulation was applied as flat sheets as thin
as 1 / 16" or as a corrugated version. If the asbestos
breaks down it can be released into the ventilation system.
Asbestos cement was a heavily used material for heating
ducts built into concrete slab floors in houses built
in the 1950's through the late 1970's. Inspection of
these is highly recommended.
Boiler wraps
Usually made of chalky blocks approximately
2" thick, they were fastened to boilers by wires or metal
straps and then coated with plaster-saturated canvas.
High humidity or water can cause it to breakdown and
disintegrate quickly. They were in use up to 1975.
Insulation
Asbestos can be found in wall, ceiling,
and attic insulation constructed between 1930 through
1950. Usually found inside of the house sandwiched between
the framing and the plaster walls. If this is found,
professionals should be called for any remodeling or
renovations.
Roofing and Siding
From the 1940's through the 1960's,
asbestos cement was commonly used for roofing shingles.
The shingles are usually gray and can bear brownish-white
streaks where water drains more slowly. They will make
a dinging sound when hit with an object. Between the
1930's and the 1970's asbestos-cement shingle siding
was also used. They can be any color and they have a
propensity to crack and chip along their edges. Although
general use was discontinued, it is sometimes still being
used. If the shingles are breaking apart, care should
be taken that the fibers do not enter the house through
open windows and doors.
Joint Compound and Textured Paint
Until 1977, joint compound used to tape
joints in wallboard and fill holes in plaster contained
up to fifteen percent asbestos. Textured paints before
1978 may also contain asbestos. Do not disturb if it
is in good condition. In 1977, the Consumer Product Safety
Commission banned patching products containing asbestos
because of their health risks.
Fireproof Board
Still being manufactured, these boards
are 1 / 4 to 3 / 4" sheets, gray in color, almost resembling
plasterboard. It can be found around wood burning stoves,
oil, coal or wood furnaces to protect the floors and
walls around them. It may be brittle so care should be
taken around it.
Asbestos Ceiling Tiles
Usually a brownish material, it can
be found in acoustic tiles that are often seen in recreation
rooms. Even today they are being made so ask the manufacturer
if there are any doubts. But as long as they are in good
condition there should be no worries.
If further information regarding asbestos
is needed, it may be obtained from the Environmental
Protection Agencies Asbestos hotline at 202.554.1404. |
