How Do Insect Foggers Work?

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Insect foggers use various chemicals to kill or repel insects like roaches or fleas inside a home. According to the Kentucky Pest News Newsletter, fog particles kill pests that are directly hit by them.


Foggers usually come in a can. The fog is activated when a tab is removed from the top of the can. It releases droplets of the pesticide into the air which then settle on surfaces throughout the home.


A 6 to 8 oz. can of insect fogger covers most homes sufficiently, according to the Kentucky Pest News Newsletter. Smaller cans are available for small homes or apartments. The EPA states that 1 oz. per 1,000 cubic feet is effective.


The main ingredient contained in most foggers is pyrethrin, a pesticide derived from chrysanthemums. Two more insecticides, permethrin and methoprene, are often included in a fogger.

Safe Use

According to the New York Department of Health, insect foggers are a fire hazard as they will explode if they make contact with an ignition source such as a hot stove top or pilot light. Always follow the directions on the insect fogger and keep people and pets out of the area being treated. Insect foggers should not be used in homes with people with respiratory conditions.


Though insect foggers kill flying insects exposed to the bomb, they do not work well on cockroaches and other crawling insects according to Michael F. Potter, Extension Entomologist at the University of Kentucky College of Agriculture. They tend to repel rather than kill these pests, making them harder to reach with other extermination methods.


Thomas Urbauer

Thomas Urbauer has been writing professionally since 2005, contributing online articles covering home and garden and other topics. His areas of expertise include gardening, business and electronics. He graduated from the University of Nebraska with a Bachelor of Arts degree in journalism and mass communications.