Eleshop offers different brands and types of extractors. In this article, we only look at the “large” fume extractors, equipped with a hose and filter box. What can you expect from such an extractor, and what should you pay attention to?
Terms
Let's start with an explanation of commonly used terms for different contaminants that can be extracted:| Term | Explanation |
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Smoke |
Mixture of a solid substance (combustion products) with air. For example, from soldering. |
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Flue gas |
Gas released during combustion. |
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Vapor / mist |
Mixture of liquid droplets in the air. |
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Aerosol |
Collective term for a mixture of solid and/or liquid in the air, with very small particles
(0.2-200µm). |
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Odor |
A smell that is negatively recieved by the brain. Odor can come from aerosols, but also from gases. |
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Gas |
State of a substance (like solid, liquid) where the substance consists of tiny molecules (nanometers, much smaller than 1µm) |
Large and small models
Eleshop offers different brands and types of extractors. In this article, we only look at the “large” fume extractors, equipped with a hose and filter box. The small extractors, consisting of a fan and filter cloth, are hardly effective for filtering, their operation is mainly based on moving smoke with a limited filtering effect for coarser particles. They can, for example, prevent smoke from coming directly into your face, but do not filter sufficiently to prevent harmful substances from entering the space.
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The differences between extractors
Eleshop sells different models for various applications. The following properties are important to compare:
| Term | Explanation |
|---|---|
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Airflow |
Speed (power) of the airflow. More airflow means that more air is sucked in. This means that with a higher airflow the distance from the pollution source to the suction nozzle can be greater. |
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Noise production |
Higher airflow (unfortunately) also means more noise, and this can be annoying. There are differences between the different brands and types; there are also quieter extractors that still produce a lot of airflow. For a comparison see this page. |
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Filters |
All extractors have HEPA filters to block harmful particles. You can read more about this in the next chapter. |
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Activated carbon |
The amount of activated carbon varies per extractor. You can read more about activated carbon in the next chapter. |
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UV |
Using ultraviolet (UV) light, harmful substances such as viruses can be killed. Some extractors have built-in UV light treatment offering a third method besides filters and/or activated carbon to neutralize harmful substances. |
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1, 2, or 4-fold |
There are different versions, where 1, 2, or 4 workplaces can be provided with extraction simultaneously. It is often also possible to seal one connection on a double extractor with a cap, to get extra powerful extraction on the other connection. |
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Accessories |
Various accessories are available. For some extractors, a (usually optional) remote control (wired) can be connected so that it does not have to be controlled on the unit itself. There are also different attachments, table clamps, suction nozzles, etc. available. |
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Filter indicator |
Depending on the brand and version, there is sometimes an indicator that shows when the filter needs to be replaced. Without such an indicator, it can be determined based on time of operation (e.g., every six months) or visual inspection can indicate if a filter needs to be replaced. |
Filters
All extractors are equipped with filters, but not every filter is the same. A large fine-mesh filter will block much more particles than a small coarse filter. Most extractors are equipped with two or three different filters. The first filter, called a pre-filter, is the coarsest and blocks visible particles such as grinding debris, flux, etc. This filter is cheap and will need to be replaced relatively often, of course depending on the use. This is important because it protects the finer (more expensive) filters. The finest filter is always placed last and is only meant to filter out the very fine particles, to maximize the lifespan.
HEPA
The filter efficiency depends on the size of the particles passing through it. Researchers have shown that particles of 0.3µm are the hardest to filter (they move through the filter the easiest). A well-known term to express how well a filter works is HEPA (high-efficiency particulate air). The higher the HEPA class, the more expensive the filter, and the more particles are blocked:
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HEPA-class |
Filter efficiency |
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E10 |
> 85% |
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E11 |
> 95% |
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E12 |
> 99,5% |
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H13 |
> 99,95% |
As you can see in this table, an H13 type filter works best to capture particles. We recommend this for professional solder fume extraction. Furthermore, especially in combination with UV light, this can also potentially filter harmful substances such as the COVID-19 virus (see current research for more information).
To remove unpleasant odors, it is not always sufficient to use only HEPA filters or UV light. These can also be caused by gases. Gases consist of molecules so small that they can easily pass through an H13 filter. Therefore, in this case, it is important to choose an extractor with activated carbon.
Activated Carbon
This is a carbon with a gigantic surface area because it is completely perforated with pores. Per gram of activated carbon, the contact surface area can be up to about 2000 square meters. Harmful gases that pass through the activated carbon will bind, making it possible to filter out unpleasant odors. The more activated carbon, the better gases and odors can be filtered out, but also the more expensive the filter will be. It depends on the application whether it is necessary to have a lot of activated carbon.
Combination
No extractor will only use activated carbon. It would immediately get clogged by the pollution; only the air that has already been purified by the HEPA filters will be passed through the activated carbon. Activated carbon can also be applied in the HEPA filter (2-in-1).
Filter Size
So far, we have talked about the fineness of filters (HEPA class), but not about the size of the filters. This is rarely discussed in datasheets, but it is important. If a relatively small filter is used, more power is needed to get the polluted air through the filter than if a large filter surface is available. This results in higher power consumption and more noise. A large filter also has another advantage; the air flows more slowly through the filter (just as a river that becomes wider will flow more slowly). This gives the activated carbon more time to react with the harmful gases, making the filter more efficient (and longer-lasting). So, there are only advantages, except for the price… The (main) filter is the most expensive part of the extractor, so most manufacturers try to cut costs here. But this is not always the right choice.
Filter Lifespan
For proper operation of the extraction, the filters need to be cleaned or replaced regularly. The frequency of this depends heavily on the use and pollution. The pre-filters are the most important, as they protect the more expensive filters. Moreover, these are relatively cheap, so they can be checked monthly, especially in the beginning. If it turns out that the pollution is not so bad, this interval can be extended. The extractor will suck less effectively if the filters are clogged, and in an extreme case, it can lead to the motor burning out. As a rule of thumb, you can assume that all filters need to be replaced about once a year, but if only a little soldering is done a few times a week, the filters may last much longer.
Conclusion
Depending on the application, there are many configurations possible in terms of extraction. If good filtration is important for your application, especially for the extraction of odor and/or gases, please contact us. We can advise you on the right filter, specifically suited for your application, whether it is laser engraving, solvents, or solder fumes.
Some examples:
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