Fumigation
Fumigation is a means of disinfection by use of fumes or gases, and is used generally for the purpose of destroying germ life only on the surface of objects. For this reason fumigation should not be used as a substitute for disinfection. Formaldehyde and sulphur dioxide are used largely for fumigating purposes.
Of these two gases formaldehyde is the better since it is not poisonous, does not injure the surface of objects and will not damage the most delicate fabrics nor destroy colors. Sulphur dioxide is very destructive and therefore less desirable. However, all the gaseous agents lack sufficient penetrative power to accomplish more than a surface disinfection. Formaldehyde is a good germicide and this adds to its efficiency.
To obtain the desired results in fumigating there must be special attention given the preparation of the rooms or spaces to be fumigated. All objects in the room should be so exposed that the gas may readily get to all surfaces. All furniture and other objects should be moved into the room away from the walls and all doors and drawers of bureaus and boxes should be opened so the gas may find free access to every nook and corner. Much of the gas may escape through cracks and crevices, therefore special care must be exercised that these openings are all properly closed before the fumigation is started. In view of the fact that the gas is non-destructive there is no harm done even to the most delicate materials.
The best results are obtained from the formaldehyde when the temperature of the room is 65° F. or over, with a relative humidity of at least 60%. While formaldehyde has the power to kill spores it is not considered sufficient to disinfect in such dis-eases as anthrax and tetanus.
Formaldehyde gas kills all forms of microörganisms almost instantly but is not particularly destructive to higher form of life. It produces a marked irritation in the mucous membrane of the respiratory tract which may result in death to animals exposed to the gas for any length of time. It is not considered an insecticide.
In fumigating a room with formaldehyde great care must be exercised that the individual does not remain in the room after the gas begins to be liberated. After the process of fumigation has been completed the windows and doors should all be opened that the gas may escape. It is always best to have the doors and windows open from the outside so that it will not be necessary for any one to go into the room until the gas has blown out.