MICROBIOLOGY OF AIR
Air
is a carrier of particulate matter, dust or droplets which may be laden with
microbes. Organisms introduced into the air, can survive for many months or die
in a few of seconds, in relation to the resistance of species to the new
phisical environment.
Airborne microbes constitute a hazard as
contamination to laboratory and home. There are several devices to effect the
sampling of air. There are solid and liquid impingement devices. In solid
impingement devices, microbes are impinged on the solid surface of an agar or
filter disk. Then, they are passed through a liquid as a broth. Finally, aliquots
of liquid are cultured to determine their microbial content.
The
numbers and types of microbes contaminating the air are determinated by the
source of contamination. Organisms contained in the air above the ocean and
those contained in the flora of the upper atmosphere are capable of surviving
to temperature and humidity changes and to a solar radiations.
Microbiologists are concerned with the fact
that all laboratory tecniques produce aerosols. If the microbe under study is a
pathogen, there will be a hazard to laboratory workers, which can acquired
infections.
Air hygiene is of great importance because some
infections agents can be airborne. Certain operations require that air be
sterile, such as the air contained in a culture tube. There are industrial
processes that require organisms grown in a pure colture under aerobic
conditions. The level of air contamination can be reduced or sterilized as the
situation demands.
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