561 
and other infections liable to be conveyed by the milk. This milk is 
to be delivered in sterilized containers, and is to be kept at a tem- 
perature not exceeding 50° F. until it reaches the consumer. It shall 
contain not more than 100,000 bacteria per cubic centimeter. 
CLASS 3. PASTEURIZED MILK. 
Milk from the dairies not able to comply with the requirements 
specified for the production of milk of classes 1 and 2 is to be pasteur- 
ized before being sold, and must be sold under the designation “ pas- 
teurized milk.” Milk for pasteurization shall be kept at all times at 
a temperature not exceeding 60° F. while in transit from the dairy 
farm to the pasteurization plant, and milk after pasteurization shall 
be placed in sterilized containers and delivered to the consumer at a 
temperature not exceeding 50° F. All milk of an unknown origin 
shall be placed in class 3 and subjected to clarification and pasteuri- 
zation. No cow in any way unfit for the production of milk for use 
by man, as determined upon physical examination by an authorized 
veterinarian, and no cow suffering from a communicable disease, 
except as specified below, shall be permitted to remain on any dairy 
farm on which milk of class 3 is produced, except that cows which 
upon physical examination do not show physical signs of tuberculosis 
may be included in dairy herds supplying milk of this class, although 
they may have reacted to the tuberculin test. 
This milk is to be clarified and pasteurized at central pasteurization 
plants, which shall be under the personal supervision of an officer or 
officers of the health department. These pasteurizing plants may be 
provided either by private enterprise or by the District Government, 
and shall be located within the city of Washington. 
By the term “pasteurization,” as used herein, is meant the heating 
of milk to a temperature of 150° F. or 65° C. for twenty minutes, or 
160° F. or 70° C. for ten minutes, as soon as practicable after milking, 
in inclosed vessels, preferably the final containers, and after such 
heating immediate cooling to a temperature not exceeding 50° F. or 
10° C. 
No milk shall be regarded as pure and wholesome which, after 
standing for two hours or less, reveals a visible sediment at the bottom 
of the bottle. 
No dairy farm shall be permitted to supply milk of a higher class 
than the class for which its permit has been issued, and each dairy 
farm supplying milk of a specified class shall be separate and distinct 
from any dairy farm of a different class; the same owner, however, 
may supply different classes of milk, providing the dairy farms are 
separate and distinct, as above indicated. 
24907— Bull. 41—08 36 
