a. Mercuric Compounds. The half-life for the decomposition of mercury is very
long; therefore, mercuric compounds cannot be disposed of as regular trash because
they pollute the environment. The easiest and safest method for the disposal of
mercury is to contract a local company that works with these substances. But if local
disposal is necessary, a closed steel container is suitable for accumulation pending
disposal.
b. Corrosives. Strong acids and bases are harmful because of skin burns and
inhalation. They can also be the cause of corrosion of the laboratory equipment. A
sandbox is required for the storage of these chemicals. Avoid storing strong acids and
bases together.
c. Flammables. Some liquids and solids have a low flash point and react so
violently to sudden changes in temperature or pressure that they are considered to be
explosives. When using these materials, ensure that there is adequate ventilation and
that there are no open flames in the area.
d. Poisons. Some substances can intoxicate to the extent of death, even when
small amounts are ingested or inhaled. Pipetting by mouth should be avoided at all
times. Poisons that are given to patients as fixative (PVA) must have a prominent red
label marked "POISON."
e. Carcinogens. Certain reagents, such as xylene and formaldehyde, upon
prolonged contact with the skin or mucous membranes, are suspect as the cause of
cancerous processes.
1-14. EQUIPMENT IN THE PARASITOLOGY LABORATORY
A small amount of work (cleaning and calibrating the equipment) will save a large
amount of money and time by eliminating breakdowns and repeated tests. Careful use
and maintenance of the equipment below will ensure a more smoothly working
laboratory:
a. Refrigerator. The refrigerator should be kept clean and defrosted. A daily
log of the refrigerator temperature should be maintained. Flammables should be stored
only in explosion-proof refrigerators. No food or drinks should be placed in the
parasitology refrigerator.
b. Autoclave. The autoclave should be cleaned after every use to prevent
accumulation of various deposits. The temperature and pressure of the autoclave
should be recorded for each load (the temperature chart can be used as a permanent
record). A processing indicator (autoclave tape) should be affixed to each item and a
viability test (spore-test) must be performed weekly. This information must be kept as a
permanent record.
MD0841
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