COK'STRUCTION AND FIRE PROTECTION" OF COTTON WAREHOUSES. 27 



Fire doors for protection of openings in a division wall should 

 always be arranocd to close automatically in case of fire. The ar- 

 rangement should be such that the door is held open, against its 

 tendency to close from gravity, by a device which is affected by 

 heat in such manner asj to release the door and permit it to close 

 in case of fire. The arrangement may be such that the door normally 

 is closed but may be held open by a special hook designed to release 

 the door should fire occur. All self-closing doors should provide 

 this automatic combination, as otherwise there is danger of the door 

 being purposely obstructed and then overlooked until a serious fire 

 loss has supplied a costly reminder. 



fire. The pulley over which the chain passes miLSt be sufRcienlly high to 

 insure that the door is entirely closed before the weight reaches the floor. 

 The weights used for holding open either type of sliding door (shown to the 

 right of the doors) should be adjusted to balance the door exactly and so 

 allow it to be closed by hand. The self-closing featui'e may be added to both 

 1L of these doors by omitting the weights which hold the door open. When this 

 B is done the fusible link shovild be retained and a hook provided to seciire it to 

 W the edge of the opening when it is desired to hold the door open. Unless the 

 F link and hook are provided, doors should never be self-closing, as they fre- 

 quently will be obstructed "temporarily" for the movement of goods and then 

 forgotten. If the hook is provided, it will be used as the easiest way of hold- 

 ing the door open, and if the door is, by chance, left open it will still close 

 automatically in case of fire. It should be noted that the hardware for these 

 floors provides a roller at the bottom of the door for holding it close to the 

 wall on one side, while the door is held firmly when closed by the heavy iron 

 bumpers on the other side. These doors show three hangers, the center hanger 

 serving to hold the door against buckling from heat. Two hangers are suffi- 

 cient for doors not exceeding 6 feet in width, while three hangers are required 

 for wider doors. Goods should never be piled again the door. To guard 

 against this it is sometimes desirable that a substantial slatted giiard be 

 provided. 



Drop doors, or those vertically sliding, such as is shown by figure 4, Plate 

 XIV, may be used to advantage in case obstructions such as pilasters or 

 j, buttresses interfere with the horizontally sliding door and where the height 

 of story is sufficient. In the illustration the weight shown on the left is con- 

 nected by a cord passed through two pulleys to the fusible link placed at the 

 bottom edge of the door, and when the weight is released the door closes. 

 The closing is made gradual by the large counter weight or balance shown 

 on the right. This door may be operated by hand, though it is not opened as 

 readily as the horizontal sliding door, and is particularly difficult to open 

 after the closing has been automatic. Furthermore, it presents some hazard 

 to life if it should drop while a person were passing under it, though this 

 danger is reduced by the large couutei-weight. 



The swinging door shown by figure 6, Plate XIV, is satisfactory though 

 it is better suited to small than large openings It may be arranged to be 

 self-closing or to close automatically, but care should be taken that the 

 fusible link used is placed in position to be reached by drafts of air through 

 I the opening. For this door the hardware, unlike that of the sliding or drop 

 ■ doors, must provide substantial latches which will hold the door securely 

 when closed. 



