(2) Harborages within buildings are of three types--structural, incidental, and
temporary. Structural harborages include double walls, spaces between floors and
ceilings, and boxed-in pipes and beams. The incidental types result from installation of
"infestable" furniture, fixtures, and equipment, including shelves, counters, refrigerators,
etc. Temporary shelters are those found in accumulation of rubbish, in piles of old
lumber and rocks, and among masses of materials and supplies. During a control
campaign, rat harborages should always be destroyed in order to prevent them from
being used by new rodents that may enter the area later. This also will prevent such
new occupants from becoming infested by ectoparasites that remain alive in the old
shelters when their original hosts have been killed, an important consideration in
disease control.
3-6.
PHYSICAL CONTROL
The use of physical control involves the use of devices that change the habitat
such that rodent behavior is affected or they are repelled. Recently, several
manufacturers have developed and sold sonic and electromagnetic devices, claiming
that they disrupt the rodents mating, feeding, and other habits or actually repel a rodent
from the area. None of these items have been registered with the Environmental
Protection Agency and furthermore, research has indicated that they are ineffective in
repelling rodents. Because of these factors, the DOD does not recommend the
purchase and use of these items for rodent control.
3-7.
REGULATORY
a. Laws and Regulations. Local laws and standard operating procedures are
used in the regulation of landfill operations and proper maintenance of sanitation in and
around food handling establishments, quarters, and other government facilities. Various
regulations govern standards of sanitation and procedures to be utilized at military
installations and during combat operations.
b. Retrograde Cargo. Rodent control in and around port facilities may present
some problems peculiar to that type of environment. The movement of ships from one
country to another always poses a potential threat of communicable diseases spread by
rodents and their ectoparasites. The Quarantine Service of the US Public Health
Service is charged with the inspection against and eradication of vector pests brought to
our shores by ships and aircraft. The Service maintains constant surveillance of
incoming and outgoing traffic of all ports of entry. The principles of rodent control on
shipboard and around waterfront areas are the same as mentioned previously. More
emphasis should be placed on mechanical measures to prevent the movement of
rodents to and from ships. Lighting all ramps and placing metal ratguards on all lines
are two methods in worldwide use. Shipboard fumigation and intensive poisoning
programs aboard ships and in waterfront areas are also used.
MD0172
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