Fogging Pest Control – Thermal and Cold Options

Fogging is a pest control technique that involves the use of a pesticide spray known as aerosol or the very active pyrethroid, which is a quick action pesticide used to exterminate all kinds of insect infestation.

Hot vapor can also be used instead of those pesticides, especially for those who hate to use chemicals.

Fogging can be used to control insects like mosquitoes in enclosed places like greenhouses and homes.

Fogging is also used to collect samples of insects or to study them under the shield of tall trees. Using this method, the base of the trees is lined with a plastic sheet so that when the fog causes the insect to fall, they can fall into the plastic sheet.

The insects are collected and transported to the laboratory for studying.

A fogger is a device that is used to carry out this operation. This device is mostly used outdoors like backyards, gardens, and so on, and it is effective in the fight against little pests like ants, insects, mosquitoes, etc.

Fogging can only take place in areas where you can find insects, so you have to find where they are located.

Another important thing to consider before fogging is the timing; there are times when fogging is best done, and there are times when fogging is not safe and will not effectively serve its purpose.

The devices used for fogging can be classified into; Thermal and Cold Foggers.

Another solid option is the use of automatic misting systems.

Thermal Fogger

Thermal foggers are used to combat household or farmland pests outside an enclosed area. The thermal fogger turns the liquid insecticide solution into vapor using heat. The vapor then forms a cloud of fog that penetrates every area, including shrubbery, treetops, grasses, etc.

The thermal fogger is 99.5% productive when they are used for exterminating mosquitoes

How Thermal Foggers Work

First, the fogging solution is created by mixing the insecticide with water. The best fogging solution to combat mosquito infestation is a pyrethroid. Hot water can also be effective, depending on the targeted pest.

The mixed solution is now poured into the storage tanks. An average Thermal Fogger’s storage can hold up to 10 liters of solution. Some of the fogger’s storage tanks can be found at the bottom of the fogger, while others have their storage tanks inside the body of the machine.

The Thermal Fogger’s pump is located at the front of the fogger. Using this pump, the fogging solution is sent through the heater assembly. The operator can initiate this process by pressing the fogging trigger, which can be found under the handle of the fogger for most thermal foggers.

Whenever the pump is initiated, the fogging solution goes into the heating assembly through a coil that is set at a very high temperature. Then the solution is transformed into vapor so that when it sprays the solution, what comes out of the nozzle will be in the form of a mist or a fog.

The three types of thermal foggers are;

  • Propane thermal fogger; this type of fogger uses propane to heat the coil to produce the fog. It has a socket that is found on the back of the fogger for the gas cylinder.
  • Fuel thermal fogger; this type uses fuel to heat the coil to create the fog. It has a large tank where the fuel is stored on the side for the fogger.
  • Electric thermal fogger; this fogger uses electric energy to heat the coil to make the fog. It has a power cord that has to be plugged into an electrical unit for the fogger to work.

Cold Fogger

Unlike the thermal fogger, which can only be used outdoors, the cold fogger is a device that can serve both interior and exterior purposes. Another interesting feature of this fogger is that it can be used to disinfect the home ad also help get rid of unpleasant odors.

The cold fogger is the direct opposite of a thermal fogger.

Unlike thermal fogger, they don’t turn the fogging solution into a misty vapor. Rather they make use of high air pressure to transform the solution into tiny particles- cold spraying methods.

Cold foggers are of two designs; the handheld fogger, which is less expensive, and the backpack fogger, which is easier to carry and more convenient to use.

The most common type of cold fogger is the ULV- Ultra Low Volume Fogger.

Ultra-Low Volume Fogging Machines

These fogging machines are cold fogging machines that make use of low pressures in large volumes to convert the fog solution into droplets that would be sprayed into the atmosphere.

These machines are used for applying any kind of pesticide, herbicide, fungicides, disinfectants, and any other chemicals that work when transformed into droplets.

The droplets produced by this type of machine are as small in diameter ranging from 1–150 μm.

How Ultra-Low Volume Foggers Work

The main part of a ULV fogger is the electric motor, which can be found inside the casing of the cold fogger. The electric motor is mainly responsible for converting the fogging solution or liquid into tiny droplets.

The impact of the airflow depends solely on the power of the motor. Most handheld foggers have electric motors of about 1-3 Horsepower (Hp). Meanwhile, backpack foggers have powerful motors of up to 20 Horsepower (Hp).

In the case of a ULV fogger, you can use a water-based solution, an oil-based solution, a chemical-based solution, or a combination of any of the solutions. The solution is prepared and poured into the tank, which is found in the body of the fogging machine or attached to the bottom of the machine.

A lot of ULV foggers use electricity, which means that you need to have an electric unit around the area that requires fogging- an extension cord will be of great help here.

But then, there is some cold fogger that uses a battery to power the motor, while some others use gasoline to power the motor.

The motor of a cold fogger works quite differently from the thermal fogger. The motor of the ULV fogger pumps the solution automatically. The liquid is sprayed through the nozzle that can be found in front of the fogger.

The nozzle as a result of the high-speed air through which the liquid is pumped pressurizes the air so much that it converts the fogging solution into a fog or a fine mist.

Best Time to Fog

The best time to fog will depend on the type of your target pest.

For instance, if your target pests are mosquitoes, it is better to fog when the activities of mosquitoes are at their peak. Almost all species of mosquitoes are active in the evening except for a few.

Mosquitoes generally prefer to stay in shady areas and would try as much as possible to avoid the sunlight.

Therefore the best time to fog when targeting mosquitoes will be at dawn or dusk, but I would rather place my bet on fogging around dusk.

Fogging in the evening time is more effective because the temperature would have gone down.  By this time, the temperature closer to the ground would be higher than the temperature in the air.

Mosquitoes love to stay in an area where the temperature is low, plus the lower temperature will allow the fog from the fogger to settle on the ground with relative ease, which will make the fog remain in the area for a longer period.

More so, fogging around the dusk to target mosquitoes will protect the other insects and bees from being targeted because they would have gone to their respective beds. So fogging won’t cause harm to them at that time of the day.

Also, fogging is ineffective when it is windy, which is why it would be better to fog around the dusk when the wind has died down.

Worst Time to Fog

Some periods are not just conducive for fogging and will render your operation a total waste of time.

First, you shouldn’t fog when your target pest is inactive, but more importantly, you shouldn’t fog whenever it is windy for the following reason;

  • Fogging in the windy condition is a total waste of time and energy because the insecticide or the hot vapor will not be able to reach the area you want to fog since the wind is likely to blow away the particles that are meant for the fogger.
  • A large quantity of insecticide will be wasted in the process with little or no result to show for it.
  • The chemicals contained in the insecticide are capable of harming non-targeted insects and bees, and even your vegetation.

You, your pet, and your children are not also out of harm’s way because some of the chemicals are dangerous to the health, and you become more exposed if the wind is left to dictate where the insecticide will be sprayed.

When fogging using any of the types of fogging machine, you must take the necessary precaution especially when the solution is an insecticide, because a lot of pesticides contain chemicals that may be harmful to the skin or the health.

So when fogging, ensure that;

  • You put on clothes that can protect your skin- a long sleeve shirt and long pants; you should also put on a face mask.
  • You are fogging in the wind’s direction. In as much as you are fogging in low wind, you have to make sure that you don’t stand against the wind to avoid the fog from being blown back to you.
  • You do not fog in high temperatures.

Lastly, you must know that fogging does not exterminate eggs or larvae. So if you need to get rid of the larvae or eggs, you need another fogging solution.

Oils are capable of getting rid of larvae. So, you can fill the tank with oils or a combination of the oils and water to get rid of the eggs, pupae, or larvae.

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