similar materials fb <fceal these small crevices and 
holes will facilitate cleaning, prevent entrance of 
insects, and reduce their harborage or breeding 
places. 
Cleaning may also be hampered by inconvenient 
placement of equipment. Frequently equipment 
that cannot be moved is installed close to walls, 
and the space between, which therefore is seldom 
cleaned properly, may provide harborage for insects 
and rodents. Meters, fuse boxes, pipes, braces, 
and conduits installed on or near walls or floors 
provide many hiding places for insects and rodents. 
Frequently, other conditions favoring insect and 
rodent infestation are found in food processing 
plants. These include false ceilings, poorly fitted 
doors and windows, boxed-in areas under counters 
and stairways, and improperly screened doors and 
windows. All of these conditions favorable to 
insect and rodent life can be eliminated by proper 
arrangement of equipment and storage of material 
and by minor structural alterations and good house- 
keeping and maintenance. 
In the seafood industry, large piles of oyster, 
clam, and crab shells containing fragments of flesh 
provide an attractant and a breeding place for flies, 
as well as a source of food for rats. Oyster and 
clam shells should be collected twice weekly 
during the fly breeding season and either processed 
for industrial use .. ned to the beds. Crab 
shells should be de vered to the fertilizer plant 
at least as frequently, li is important that cooling 
rooms and picking rooms in crab proc ssing plants 
be ratproof and well screened agair.st flies. 
The abattoirs, meat packing plants and asso- 
ciated stockyards of the slaughtering industry are 
frequently troubled by rodent and insect infesta- 
tions. The rats feed on inadequately protected and 
carelessly handled animal feed, and flies breed in 
large numbers in manure and in moist spilled feed. 
Correcting these conditions involves improvement 
of physical facilities. Easily cleaned concrete pen 
areas, with drains leading to sanitary sewers 
should be provided. Feeding troughs should be so 
constructed that they are easily filled and cleaned. 
To reduce the rodent and insect problem, frequent 
cleanup of manure is required, with storage in fly- 
tight containers or prompt removal to a disposal 
site where it should be buried, burned, or spread 
thinly on fields as fertilizer. 
Until such time as unwanted meat scraps and 
viscera from slaughter houses can be removed 
for proper disposal, they should be stored in a 
manner that makes them inaccessible to insects 
and rodents. 
Hog farms, described in a previous section, 
dairy plants, and chicken farms are other animal 
industries that suffer vermin infestations as a re- 
sult of human carelessness, poor arrangement of 
equipment, improper storage of materials, and 
inadequate disposal of wastes. 
Other types of commercial enterprises may some- 
times have severe insect and/or rodent infesta- 
tions. In foundries, for instance, food for rodents 
is supplied where foundry flour, used to seal the 
top and bottom side of a mold to prevent the escape 
of mo?^»n metal at the parting line, is frequently 
allowed to fall to the floor where it becomes scat- 
tered around the area. Sometimes the new unused 
foundry flour is not stored in rodent-proof bins. 
Consequently, both stored and waste flour pro- 
vide food for rats and a feeding place and breeding 
site for insects, especially grain beetles and other 
stored-food insects. Ample harborage for rats is 
often present in foundries in the form of improperly 
stored scrap, old flasks, bottom boards, and slip 
jackets. 
Insect and rodent problems are common in the 
wood and paper product industries where poorly 
stacked log piles and wood chip piles offer abun- 
dant harborage, or where salvaged scrap paper and 
cardboard with food particles adhering offer an 
attraction for flies and rodents. 
In flour mills and powdered-milk plants, it is 
important to vacuum-clean all overhead beams and 
other locations at frequent intervals to help reduce 
insect and rodent infestations. 
A problem common to all industries, in fact any 
enterprise or office where people are employed, is 
the storage and disposal of lunch-time food scraps. 
Tight metal garbage cans should be provided in 
adequate numbers and their use, in place of open 
waste containers, should be enforced. Otlierwi.se 
an infestation of rodents and insects, particular^ 
of roaches, will be encouraged. 
Mosquito annoyance may be important in and 
around industrial plants. In addition to mosquito 
breeding places previously mentioned, these in- 
sects may breed in stagnant waters in coolinu 
towers and settling basins, in waste waters from 
industrial processes including coal mines and oil 
fields, in lagoons, and in poorly drained areas 
around the plant. Many of these breeding sites ( an 
be eliminated by filling, draining, and alterati f 
construction or storage. Those breeding place a that 
37 
