How to Use Bug Bombs to Kill Roaches

Roaches repulse many people, and with good reason. Cockroaches transfer germs by crawling over household surfaces and can trigger allergic reactions or asthma attacks in sensitive individuals. Bug bombs can help control severe roach infestations, but you must be very careful to use the products correctly.

About Bug Bombs

Bug bombs, also called total release foggers, are products designed to spew all of their contents at once. You simply push a valve button to lock it into place, and the container begins discharging a fine aerosol spray to fill the air with insecticide, usually permethrin, methoprene or pyrethrins. The tiny droplets stay suspended in the air for a short time before falling down onto household surfaces. Bug bombs have their good and bad points.


Bug bombs:

  • effectively treat heavy roach infestations
  • kill roaches exposed to the spray
  • are convenient and easy to use
  • cost less than many other roach control methods


Bug bombs also have plenty of disadvantages. The products:

  • contain chemicals toxic to people, pets and fish
  • offer temporary relief because the mist doesn't reach into the nooks and crannies where roaches hide
  • often repel roaches, causing them to move deeper into walls, flooring cracks and other hard-to-reach places
  • contain flammable ingredients

Using Bug Bombs

Foggers effectively reduce cockroach numbers if you use them properly.


Foggers can only kill insects if they are used in an enclosed area, so you must shut all windows and doors leading into the treatment area. Turn off air conditioning units, fans, ventilation equipment and smoke alarms. Open all closets, cupboards, cabinets, drawers and doors in treatment areas.

Because bug bombs use flammable materials that can turn them into actual bombs, you must remove all potential ignition sources. This includes live flames, such as a lit cigarette or burning fireplace, as well as pilot lights in gas water heaters, ovens and stoves. Unplug any running electrical appliance that cycles, including air conditioning units, thermostats and refrigerators, because they can spark as they turn off and on.

In addition, you need to remove or cover:

  • exposed food
  • pet and child toys
  • eating utensils, dishes, pet bowls and food processing equipment
  • food prep surfaces
  • wood furniture and floors in the area surrounding the bug bomb.
  • electronics in the treatment area

Make sure no humans, pets, birds or houseplants remain in the treatment area due to the toxicity of the chemicals. If you have fish, cover and turn off the aquarium.

Fill out the door hanger that comes on the box or make your own warning sign. Hang it on the front door so friends, family members or neighbors won't enter during the fogging treatment.

Place a stool, stand, small table or chair in the center of the room to be treated. Cover it with old newspaper, paper towels or a dropcloth to protect the surface.


Decide how many bug bombs you need by figuring out the cubic feet of the treatment area. You do this by multiplying the area's width by the length by the height. The California Department of Pesticide Regulation recommends not using more than 1 ounce of product for every 1,000 cubic feet of treatment space.

In addition, never use more than one bug bomb per room and avoid placing a fogger inside of small spaces, including cabinets, closets, beneath tables or counters and in rooms smaller than 5 feet by 5 feet. Allow the mist to enter the enclosed area from other rooms instead.

Carefully following the instructions on the product's label, point the nozzle away from your face and press the valve button to lock it open. Set the activated bug bomb on the prepared stool or surface and vacate the premises immediately.


Stay away from the premises for the amount of time indicated on the product's label, typically two to four hours. When you return, open all windows, doors and vents.

Allow the house to air out for the length of time the manufacturer recommends, which can be anywhere from 30 minutes to two hours. Allow the space to air out even longer if you can still detect an odor when you return.

Turn on fish aquariums and reconnect smoke alarms once the room finishes airing out. Clean all exposed surfaces in the treatment area, including food prep areas, counters, tables, floors and any surface that children or pets might touch.