In this article, we’re going to look at the advantages and disadvantages of both thermal and cold foggers. Let’s start with thermal foggers.
Thermal Foggers: Advantages
The thick, visible fog
One of the major advantages of thermal foggers is the fog itself. Since thermal foggers use heat to vaporize the fogging solution, it forms a thick cloud of fog that can be white or grey. ULV foggers that use cold fogging techniques, on the other hand, produce a practically invisible fog.
A highly visible fog has a few advantages, such as:
- It’s easy to control and monitor the flow of the fog. For many applications, you’ll need to control and direct the fog to reach certain areas, such as the foliage of plants, treetops, and other areas. Since the fog produced by thermal foggers is highly visible, it’s very easy to aim the fog towards certain areas and see that it hits its target.
- If you are an operator, the visible fog provides peace of mind to your clients who can actually see you doing something to combat their problem.
- It’s easier for the fogger operator to avoid direct contact with the fog. This is also true for bystanders. Since the fog might contain substances that are not good for your health, being able to see it makes it easier to avoid.
Smaller droplets and a higher droplet density
The droplets produced by thermal foggers are very small and can even get as small as 0.5 micron in diameter. Because of the small droplet size these foggers produce, they can spray a higher density of droplets. Both of these factors make thermal foggers perfect for insect control applications.
The particles produced by thermal foggers can penetrate very small areas. In outdoor applications, the smaller particles will stay in the air for a longer amount of time. This will increase the chances that fog will come in contact with flying insects such as mosquitoes.
Can use water- or oil-based solutions
Thermal foggers allow you to use both water and oil-based solutions. Water-based formulations are a lot more environmentally friendly, can be used to fog plants, and don’t pose a fire hazard. Furthermore, water-based solutions don’t cause equipment corrosion and are cheaper than oil-based solutions.
Thermal foggers are more efficient than cold foggers in a few ways. They can:
- Use a low concentration of the insecticide.
- Spray more insecticide using less energy than ULV foggers.
- Treat an area of the same size in a shorter amount of time than cold foggers can.
Thermal Foggers: Disadvantages
Use a lot of fuel
Possibly the biggest disadvantage of thermal foggers is that they use a large amount of fuel. In most personal-use foggers, this is propane gas. Thermal foggers have to use some sort of fuel to heat the heater assembly and this has some drawbacks, such as:
- The high cost of the fuel used in thermal foggers. You’ll have to refill or change these when they run out, which can happen pretty often if you need to fog larger areas. This can make the fogging more expensive.
- The fuel can have a strong odor that may be unpleasant for the person operating the fogger and other people in close range.
- These substances can leave oily stains that are hard to clean, which is a problem for indoor fogging.
- Propane is flammable.
Because of the dense fog they produce, thermal fogging can cause traffic hazards. This is especially true when using high-capacity professional thermal foggers.
Thermal foggers work with very high temperatures. This means that the heater assembly part of the fogger can get very hot while in operation and so using the fogger can cause serious fire risks (as well as burn risks to operators if improperly handled).
A high-capacity, powerful, professional thermal fogger will be very loud when operating. This can limit the use of that fogger in urban areas.
Small droplet disadvantages
Small droplets have significant advantages over larger particles when it comes to mosquito control. But there are also some disadvantages to smaller particles. The biggest disadvantage is that they can be easily moved in any direction by smaller wind gusts. This will make fogging in windy conditions more difficult.
Cold Foggers: Advantages
Use less fogging liquid and fuel
Ultra-low volume (ULV) foggers, as the name suggests, use a low amount of fogging liquid. This results in a lower cost of application. A ULV fogger uses air pressure to atomize the fogging solution into very small particles.
Cold foggers also use electricity or battery power instead of propane fuel. This means that the disadvantages of fuel use that apply to thermal foggers don’t apply to cold fogging devices. The advantages of this include:
- They are cheaper to use since you won’t need to buy additional fuel.
- They won’t produce any hard-to-clean oily residues.
- Low fire risk and virtually no burn risk to operators.
- ULV foggers are practically odorless on most occasions. This makes them much more pleasant to use, especially indoors.
Can use water- or oil-based solutions
Like thermal foggers, ULV foggers can be used with water or oil-based insecticide preparations.
No traffic hazards
Cold foggers produce a practically invisible cloud of fog. This won’t cause any traffic hazards, so you can use this type of fogger in cities and other crowded places.
Electric ULV foggers are generally quieter than thermal foggers, which is useful in urban areas where noise may be an issue.
Cold Foggers: Disadvantages
A practically invisible fog
The fog produced by a cold fogger is practically invisible. This has its advantages, such as avoiding traffic hazards but also has some disadvantages. First of all, it’s much more difficult to monitor and control the direction of an invisible fog, especially when fogging outdoors. This is a disadvantage for mosquito control applications.
For example, if you’re fogging outdoors with some wind, the fog will drift away from your target area. With the visible fog from thermal foggers, you can easily observe this and try to correct it by more precise application. With a cold fogger, on the other hand, you won’t be able to see where exactly the fog is drifting to, so it’ll be much more difficult to direct it to a certain area.
Also, bystanders won’t be able to see any signs of fog. This means they won’t be able to avoid it and might inhale insecticides or get them on their skin.
Difficult to maintain and repair
Cold foggers require greater technical skill and are more difficult to maintain and repair. They have an electric motor, air pressure pumps, and complex nozzles that will need to be both calibrated and repaired by a trained professional.
ULV foggers produce larger particles than thermal foggers. These usually range from 10–50 microns in diameter. While you can adjust the size to fit different applications, a cold fogger simply can’t match the high-density, small droplet output of a thermal fogger. In indoor and outdoor applications, this means that the fog won’t be able to penetrate the smallest and most difficult to reach places. For mosquito control, larger particles will stay in the air for less time and won’t have as great of a chance of reaching all of the airborne mosquitoes in the area.
Cold foggers will need more time to fog a similar-sized area than a thermal fogger would due to the smaller volume of insecticide and fog itself.