34 BUILDING AND EQUIPMENT 



tern should be adequate to afford ready and quick escape of steam, 

 to remove foul air and to facilitate the regulation of temperature. 

 Unless free steam does promptly find an exit from the factory 

 rooms, it condenses on the walls and ceilings, making them sweat 

 profusely, causing corrosion of the walls and ceiling, deterioration 

 of motors and other similar equipment, and molding of supplies; 

 this is especially the case during the winter months. The removal 

 of foul air and the control of the temperature of the air are essen- 

 tial for the comfort, health and efficiency of the employes. 



The system of ventilation that will accomplish efficient ventila- 

 tion will of necessity vary with the type of plant and arrangement 

 of equipment. Gravity ventilation, such as is represented by the 

 King system is, under average conditions, inadequate to produce 

 satisfactory results in factories, like milk condenseries, where there 

 is bound to be much escape of free steam. The exchange of air is 

 not rapid enough to remove the steam before it condenses on the 

 walls and ceilings, especially in cold weather. It is, therefore, ad- 

 visable to provide for some form of forced ventilation. Under cer- 

 tain conditions of construction an air flue connecting with the smoke 

 stack may furnish all the ventilation needed. 1 Under many other 

 conditions, however, it is necessary to hood that equipment from 

 which free steam escapes in large volume, such as can washers, and 

 can sterilizers, hot wells, etc., and to draw the steam away through 

 ducts of adequate size by one or more motor fans located in the 

 outside wall or ceiling. 



Drainage. All floors of the manufacturing rooms should 

 slope to facilitate rapid drainage. A fall of one-eighth inch per 

 foot is usually sufficient. Large water-sealed floor drains should be 

 sufficiently numerous and well placed in all rooms to rapidly carry 

 off water. The surface of these floor drains should be about one- 

 half inch below that of the adjoining floor, so as to catch the water 

 readily. In the larger rooms open drain-ditches in the cement floor, 

 six to eight inches wide and covered with perforated iron plates, are 

 preferable to bell-traps. They may be placed along the walls or 

 elsewhere. They should be not. more than forty feet apart and have 

 a fall of one-eighth inch to the foot, with the floor sloping toward 

 them. It is generally most convenient to have all the drain pipes 

 enter into one large sewer pipe not less than ten inches in diameter, 



1 In this case there should be an inner and outer stack with an air space 

 between which connects with the air flue. 



