MILK -PLANT OPERATION 
19 
In the case of the plants using the brush washer there is no definite 
relation between man-hours used and the size of the plant. It will be 
seen in the columns "Number of bottles washed per man-hour" and 
"Number of man-hours used per 1,000 bottles washed" that there 
is no regular increase or decrease in those figures with the size of the 
plants. At small plants using the brush washers the men are usually 
shifted from one kind of work to another and the work of bottle 
washing is not so well systematized as is the case at larger plants. 
At the plants using the automatic machinery the larger plants are 
able to economize on labor. On account of the large volume of 
work of a similar nature that has to be done, such plants naturally 
use special efforts to eliminate all labor not essential, and use special 
men for each type of work. 
One of the outstanding points illustrated by the data in Table 6 
is the large variation in the quantities of labor required at the various 
plants of similar size using the same type of equipment. For example, 
at 12 plants washing from 10,000 to 20,000 bottles daily with auto- 
matic washers, the number of bottles washed per man-hour varies 
from 780 to 2,169. Apparently the less efficient plants in this group 
could reduce their labor costs by adopting the methods used at the 
more efficient plants. The most obvious cause of such variations 
seems to be the arrangement of the various plants. Many plants 
are very inconveniently arranged, so that extra men are required to 
transfer the bottles from place to place, and in many instances some 
of these men could be eliminated by a rearrangement of the rooms 
and equipment in the plant. 
It will be noted in the table that at plants washing more than 
5,000 bottles daily with brush washers the work is done even less 
economically than at the smaller plants. The average number of 
bottles washed per man-hour at the larger plants is only 297, while 
the average for all plants using brush washers is 323. From a study 
of the figures in Table 6 it seems evident that such plants could operate 
more economically if they would install automatic bottle washers. 
In the group of plants washing 10,000 bottles or less daily with 
automatic machines, an average of only 1 man-hour is required per 
1 ,000 bottles washed ; while in the group of plants using brush washers, 
an average of 3 man-hours is required to wash 1,000 bottles. 
Table 7 shows the average numbers of bottles washed per hour 
and per man-hour at 111 plants, using the methods (1) automatic 
machine, (2) brush washer, and (3) swabbing out with a hand brush. 
The variations in the man-hour requirements with the various 
methods are also shown. 
Table 7. — Hours of labor {average) used in washing bottles, also variations in number 
of bottles washed per hour, man-hour, and machine-hour , at 111 plants using the different 
methods. 
Method of washing. 
Automatic ma- 
chine. 
Brush washer. 
Hand washing. 
Number of plants 
Number of cities 
Bottles washed per hour 
Variation 
Variation in number of bottles washed per machine- 
hour « 
Bottles washed per man-hour 
Variation 
Man-hours used per 1,000 bottles washed 
56 
15 
4,628 
1,296 to 11, 111 
1,296 to 7,916 
1,002 
281 to 2,519 
1 
49 
10 
928 
233 to 3, 200 
233 to 2, 400 
323' 
200 to 800 
3 
3 
433 
180 to 950 
199 
135 to 266 
5 
