Guarding against explosions.--Apply a coarse spray. It is effective and safe to use. A concentrated fine mist is ineffective and may explode in the presence of a spark or flame. Do not smoke while spraying. Shut off pilot lights. Pressure.--In spraying, use only enough pressure to wet the surface of the wood. Too much pressure may cause spray to splash onto the body. If you apply the insecticide in an enclosed place, make sure that the air can circulate freely. Keep doors and windows open; if necessary, use a fan. The purpose is to prevent odors from accumulating in the building. If you treat a floor that has a finished ceiling under it--for example, the floor of a second-story room--avoid applying too much material. If you do, it may run through to the ceiling and cause a stain. Removal of the floor finish before applying the insecticide makes it unnecessary to apply a large amount; the wood absorbs most of it. If you apply the oil solution to parquet flooring, do it very lightly. If you apply too much, the oil may dissolve the asphalt in which the flooring is set. The dissolved asphalt may stain the floor. Around the edges of the floor, it may "creep up" and damage the walls. If you have applied insecticide with a garden sprayer, rinse out the tank and hose before putting the sprayer away. This prevents the gaskets from shriveling and keeps oil from getting on plants the next time the sprayer is used in the garden. Food cabinets.--In treating a food cabinet, do not use an insecticide because it might contaminate food. Use deodorized kerosene alone. It has little odor and evaporates quickly. Take the cabinet outdoors to treat it, and leave it there until the kerosene odor disappears. Fumigation.--The fact that fumigation work must be done by a licensed operator is stated on page 7. Only isolated buildings can be safely fumigated. If an apartment, a row house, or part of a duplex were fumigated, the gas might penetrate walls and kill persons in an adjoining unit. Methyl bromide gas is odorless, but in the presence of articles having a high sulfur content, or containing animal matter, sponge rubber, or iodized salt, a chemical change takes place and a garliclike odor is apt to be given off later. Before this gas is used, see whether such articles are in the building; if they are, remove them. This need not be done if hydrocyanic acid gas is used. However, hydrocyanic acid gas tarnishes silver and spoils unexposed photographic film; before it is used, remove silver and film. Prepared by R. A. St. George and T. McIntyre, entomologists, Division of Forest insect Research, Forest Service Washington, D.C. · Revised November 1959 U.S. GOVERNMENT PRINTING OFFICE: 1959 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington 25, D.C. - Price 5 cents Transcriber Note Illustrations moved to prevent splitting paragraphs.