Household Insecticides are usually applied as liquids and may come in aerosol cans or trigger pump spray applicators. They may be either residual or non-residual. Both are convenient to use and can be effective at controlling pests exposed to human skin and air. However, they cannot be effective in controlling pests that live within the walls, attics, and other areas of the residence. In addition to these risks, insecticides can also damage the environment.