28 BULLETIN 973, U. S. DEPAKTMEXT OF AGRICULTURE. 
outward, will often greatly assist in reducing the number of 
flies that enter the building. These fans provide a constant breeze, 
which forces many of the flies out as the doors are opened. Fans 
placed near milk apparatus, such as open coolers, also tend to keep 
flies away from the apparatus and out of the milk. Good ventilation 
is essential. (See Department Bulletin No. 8 19, " City Milk Plants.") 
Keeping a milk plant clean is a simple matter if one bears in mind 
the fundamentals of sanitation and has a fair idea of bacteriological 
principles. Everything with which the milk comes in contact should 
be kept clean from a bacteriological standpoint — that is, thoroughly 
sterilized with steam. Milk should be exposed to the air as little as 
possible; it should be pasteurized at 145° F. for 30 minutes and then 
kept at 50° F. or below until delivered. 
The delivery outfit is another item that should receive attention 
in respect to cleanliness. Many dealers naturally take great pride 
in the cleanliness of their plant. The delivery outfits should not be 
forgotten, for customers have an opportunity to see them every day, 
while only a few ever visit the plants. The horses should be kept 
in good condition and well groomed, the harnesses clean and well 
oiled, and wagons well painted and washed. Drivers should be clean, 
neatly dressed, courteous, and obliging. Many a good customer has 
been lost by a discourteous driver, while many a new one has been 
gained by a polite and obliging one. A uniform or a white suit 
adds much to his appearance. Where cash sales are made in office 
buildings or other places in which the customer deals directly with 
the driver this is especially desirable. 
WASTES INCURRED IN HANDLING MILK. 
One of the aims of the milk-plant operator is to keep the losses in 
the plant as low as possible. These losses vary considerably at dif- 
ferent plants, depending mostly on the competence of the men in 
charge. 
There are many items which should be borne in mind by the milk- 
plant operator in keeping down losses. The following items are 
important: 
Avoid milk piping as much as possible by the proper arrangement of rooms and 
equipment. Not only is the piping difficult to keep clean, but it causes extra labor. 
Besides, considerable milk will stick to the pipes at the end of the run, and extra 
piping will increase the loss of milk. 
Avoid use of milk pumps wherever possible by use of the gravity-flow system. 
Extra labor is required for cleaning pumps, and the gravity system is more sanitary. 
Keep a close watch for leaks, spillage, slop, etc., in the milk handling, so as to 
keep the shrinkage as low as possible. 
Drain cans well after dumping the milk. 
Have milk vats set so that they can be readily drained. 
Keep all joints in milk pipes tight to avoid leaks. 
Utilize all milk returned by drivers, and drain the containers after dumping. 
- Shut down motors or other machinery as soon as through using them, and thus 
avoid power waste. 
Avoid extra shafting, pulleys, etc. 
Avoid extra steam piping by proper arrangement of rooms, and thus avoid losses 
due to condensation of steam. 
Keep steam valves and joints well packed to avoid leakage. 
Keep all mac hin ery well oiled, but avoid waste of oil by careful use and by catching 
the drip. 
Avoid water wastes. Save water from cooler coils and from condenser coils when- 
ever possible. Too much water used in washing also requires extra washing powder. 
Water hose should not be left running when not needed. 
