Mosquito Misting Systems

Outdoor Residential Misting Systems

An increasing number of households have purchased timed-release outdoor residential misting systems to control mosquitoes and other insects around the home. However, advertisers, the media, and other sources sometimes provide information about misting systems that is difficult to understand or might conflict with other information. This fact sheet page will help consumers:

• decide if residential pesticide misting systems are appropriate for their home
• understand safety precautions about using outdoor misting systems
• find related information on Integrated Pest Management -- using a variety of methods for mosquito control
• understand the role of the EPA and state agencies in regulating misters.

Check your instruction manual or contact the manufacturer if you have questions about how to operate or maintain your home misting system.

Please note, this page does not address use of misting systems in livestock barns, boat docks, or in or around restaurants, factories, or other public spaces. More information about regulating and use of pesticides.

• What are outdoor residential misting systems?
• What pesticides are used in the misting systems?
• Are residential misting systems safe?
• Are residential misting systems effective in controlling insect pests?
• Are misting systems regulated by EPA or the states?
• Installing and using misting systems
• In case of an emergency

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What are outdoor residential misting systems?

Outdoor residential misting systems (sometimes called "mosquito misters") are application systems designed to spray pesticides in a fine mist to kill mosquitoes and other insects outdoors. Misting systems include spray nozzles that are mounted around the perimeter of a home in the lawn or landscaping, or on parts of the house or fence. The spray nozzles are connected by tubing to a supply of insecticide. Some misting systems may be turned on at preset intervals using a timer. Others may be turned on using a remote controller, while others may be activated using a switch.

What pesticides are used in the misting systems?

The insecticide products most often used in outdoor residential misting systems contain pyrethrins and permethrin. These products may also contain piperonyl butoxide. To be sure what type of insecticide you are using, check the list of active ingredients on the container label.

Certain minimum risk pesticides may also be used in some misting systems. Although not regulated by EPA, many states do regulate these pesticides. Check with your state agency  about any requirements or warnings you need to be aware of before you use the pesticide. EPA has not evaluated the potential risk or effectiveness of these minimal risk chemicals in misting systems.

It is illegal to use a pesticide in a misting system if the pesticide label contains a prohibition against use in these systems.

Are residential misting systems effective in controlling insect pests?

EPA, as well as the Centers for Disease Control and Prevention (CDC) and many mosquito control professionals, believe that a combination of approaches generally known as Integrated Pest Management (IPM) is most effective at combating mosquito populations.

Outdoor residential misting systems have not yet been studied sufficiently to document their effectiveness in controlling mosquitoes or other yard and garden pests, nor have they been scientifically proven to control or prevent the spread of West Nile Virus or other diseases.

While pest management begins with you, effective mosquito control is often community-based. Contact your local health department or mosquito abatement district to report severe annoyance or potential mosquito sources.

For pests other than mosquitoes, a combination of pest management practices tailored for the specific pest may offer the best results.

Are residential misting systems safe?

People and pets may be exposed to pesticides used in a residential misting system through direct contact with sprays, by touching plants or other objects in the treated area, or by inhaling small amounts of pesticide remaining in the air. EPA has assessed the human health and environmental risks of the pesticides most commonly used in misting systems. Most of these pesticides last only short periods in the environment, so long-term exposure to humans is not expected. Based on its assessment, using toxicity data and exposure estimates, EPA does not expect risks of concern to humans when these chemicals are used in outdoor residential systems according to labeling specific for use in these systems. However, excessive use or accidents may pose risks. No pesticide should be regarded as 100% risk free.

Since pyrethrins and permethrin are toxic to all insects, they may kill beneficial insects such as honeybees, ladybugs, butterflies and other non-target species. In addition, permethrin is very highly toxic to fish.

EPA's most recent regulatory reviews of the pesticides commonly used in misting systems are available:

• Permethrin
• Pyrethrins
• Piperonyl butoxide

EPA has not evaluated if other pesticides can be labeled for use in these misting systems without possible harm to human health and the environment.

Are misting systems regulated by EPA or the states?

• States

  Regulations for these systems may vary from state to state. Some states may forbid the use of certain pesticides, or any pesticides at all in these systems in residential areas, others may require that signs be posted, while others may not regulate their use at all. For the most updated and accurate regulations in your state, consider consulting your state pesticide regulatory agency  for details before you purchase, hire a company to install, or use a misting system.

• EPA

  EPA does not regulate residential outdoor misting system equipment. Misting system components are considered "application equipment" and therefore are not regulated by EPA. Misting systems also are not classified as "pesticide devices."
  
  EPA registers pesticides that may be used in misting systems. EPA examines the ingredients of the pesticide; the particular site on which it is to be used; and the amount, frequency, and timing of its use. EPA evaluates pesticides to ensure that they will not have unreasonable adverse effects on humans, the environment, and non-target species when used according to label directions.

Installing and Using Misting Systems

When using a misting system, following a few simple guidelines will minimize potential exposure to people, pets, and the environment.

When Having a System Installed:

• Always use installers and service technicians that comply with the state's license, certification, and registration requirements.
• Make sure that the installer has calibrated the system to apply no more than the maximum daily application rate as specified on the pesticide label.
• Make sure the nozzles are directed to spray toward the target area and away from eating/cooking areas and any water body including swimming pools and fish ponds (some pesticides are toxic to aquatic organisms).
• Placing nozzles less than 10 ft from the ground will reduce chemical drift. Chemical drift may affect other people, animals and surrounding environment not in your yard area.
• Set nozzles to direct mist away from outside air conditioners or other home air intakes.
• Make sure both the reservoir and operating system are securely locked and inaccessible to children at all times to avoid potential poisoning accidents.
• When practical, install wind, rain, and motion sensors to reduce unnecessary pesticide usage and inadvertent application when people or pets are present.

When Using a System:

• Do not apply the pesticide when people, pets, or foods are present.
• Set automatic timers for times when people and pets are unlikely to be sprayed.
• Only use the system when pests are most active. For example, certain varieties of mosquitoes are most active in the early morning and evening hours.
• Avoid using the system during high wind (>10 mph), rainfall, fog, or when outside air temperatures fall below 50 Fahrenheit or other times when insects are generally not active.
• Obtain and READ the pesticide label to know the pesticide precautions and its appropriate use in the system.
• Be aware of the maximum daily rate specified on the product label and how your system operates.
• Be a good neighbor - some neighbors may have sensitivities to the pesticides or object to drift of chemicals onto their property.
• Avoid damage or misuse from a leaking or malfunctioning system - regularly maintain and inspect it.
• Turn the system off when not needed for extended periods of time.

In Case of an Emergency

It is important to understand that improper installation of a misting system, over-exposure to pesticides, or unforeseen incidents can lead to serious injury to you and your family and others, as well as to the environment.

• Equipment leaking or not working right?

  • Turn off the system immediately and contact your installation company.
  • Ask the company about any safety precautions you need to follow.
  • Always - keep children and pets away from pesticides and pesticide equipment.

• Keep handy for emergencies:

  • EPA Registration number of the pesticide used in the misting system
  • Phone numbers for:
    • National Poisoning Hotline at (800-222-1222), More about poison emergencies
    • Your local fire department or emergency responder
    • National Pesticide Information Center at 800-858-7378
    • Your service technician