I have been working in dusty environments all my life and frankly, dust control was not a part of my daily routine. With all the information available to me, I now know some wood dust is carcinogenic. This fact is alarming considering all the dust I have taken into my lungs over the years.
My habits have changed
With this new-found knowledge, I take more care and spend more attention to detail as regards to dust control. I have cyclonic action shop vacs and dust extractors attached to the machines which help greatly but I know it does not end there.
Fine particles are airborne during work or just from a cleanup. Proactively going around with a broom is prone to disturb those finer dust particles. Anything that enters the atmosphere is likely to be inhaled so we need to investigate new ways of tackling this problem.
So let me share with you my experience regarding controlling fine dust. But first, let’s explore the problem and options available to us.
Types of Air filtration
- Central systems of air filtration
- Standalone air filtration
- Personal air filtration
- Dust extraction
As the name implies a central system for the removal of fine dust is an extraction unit which is mounted in or outside the workshop. The air is sucked into the unit by ducts which are positioned in strategic places in the workshop usually near dust-producing culprits.
What are the benefits of a Central system?
- Central systems are best mounted in another space so noise is not a problem.
- You have a choice where you want the extracted air to be vented
- Large filter boxes can maintain long term efficiency with cleanable filters
What are the negatives of a central air filtration system?
- If mounted externally you are risk of pumping out expensive heat during the winter season.
- Units can be large and take up a lot of space
- The cost can be prohibitive
Standalone Air Filtration Purifiers
Freestanding or wall-mounted dust filtration systems are a practical and cost-effective solution to dust control. I have two units in my shop but I am experimenting with new systems as my business expands. I currently have a ‘Microclene’ and an ‘Axminster’ which are ok for smaller workshops but I wish for a more effective method of controlling dust.
What are the positives of a standalone workshop air filtration system?
- Can be fairly compact
- Lower cost compared with centrally mounted systems
- Filtered warm air is not pumped out
- Can be wall or ceiling mounted
What are the negatives of standalone air purifiers for the workshop?
- Generally less efficient than larger central filter units
- Filters need very regular cleaning
- Small m3/hr volume of air filtered
Working with wood you would think we are safe from dangerous cancer-causing gases. Sadly this is not the case as we woodworkers don’t just have the fine particle dust to contend with but also Formaldehyde Gas. It is thought that Activated Carbon is capable of filtering Formaldehyde from the air we breathe in the home and workshop. The Levoit LV133 carbon air filter will improve the air you breathe.
I have written a Blog about Formaldehyde here
Personal Air Filtration
Sounds interesting? Sorry but I am about to disappoint you! Personal air filtration is just a Dust mask respirator. I feel I have to mention the obvious as it is still the most efficient method of filtering air before it can enter the pulmonary system of the lungs. Face masks are cheap and come in so many different formats which is just too much to go into detail here so check out our blog on dust masks here.
Availability of dust masks in 2020 is a problem because of Coronavirus and the mass shortage of face masks in general. I have written about the problem of dust mask supply because of COVID-19 which you can read here
Dust masks vary very much on quality and effectiveness and cost. Be very careful about using a face mask that comes free with your new tool or that is crazy cheap. Face masks come in a variety of efficiencies, for instance, the well known recommend filtration standard is the N95 but there are others that are fine for dust control.
Dust mask categories
Types of dust mask in the USA
Respirator Oil resistance ‘Niosh’
- N: Not resistant to oil
- R: Resistant to oil
- P: Oilproof
Each of these categories of the mask is available in different particle efficiency
Example1 N95: Not resistant to oil but 95% efficient at filtering particles down to 0.3 micron
Example 2 P100: Resistant to Oil and 100% efficient at filtering particles down to 0.3 micron
Types of dust mask in the UK and mainland Europe
- P1 or FFP1 (80%)
- P2 or FFP2 (95%)
- P3 or FFP3 (99%)
P2 VS FFP2
This category of mask refers to the shape of the mask
Types of dust mask in Korea
- KF80 (80%)
- KF94 (95%)
- KF99 (99%)
What are the positives of the dust mask?
- Dust masks are cheap
- They prevent pathogens from entering your lungs
- Many different types to choose from
- Some fit very well
What are the negatives of the dust mask?
- Some fit very poorly
- Face masks are hard to source during a viral pandemic
- Some cheap Chinese face masks are fake
- Many face masks are uncomfortable to wear for long periods
- Face masks can harbour bacteria or viruses
- Communication is difficult when wearing face masks
The concept of ionizing the air for the purpose of dust control is not new but is very effective. These electrostatic precipitators use charged ions to clean the air. The coronas are components which fire ion streams into the air. No, not Ghostbusters! But a great way to attract the dust particles and leave them attached to a special collection electrode.
Electrostatic Precipitators are usually a component of the centrally mounted air filtration units. This method of dust collection has commonly used as a part of the airflow stack of filters and usually accompanies true HEPA filters as a part of a three, four or five-stage system.
What are the positives of the Ionizer air filtration?
- Highly efficiency
- A good solution for central systems
What are the negatives of the Ionizer air purification systems
- Ionizer air purifiers are expensive
- Can be quite large
Dust Extraction installation
So why don’t you just use a dust extractor?
You could but these machines use a lot of electric and are noisy. Frankly not an option in real for the following.
What are the positives of using a dust extractor for fine dust collection?
- None, because this is not a viable fine dust control system.
What are the negatives of a dust extractor?
- They can be very noisy
- Can be very inefficient
- Static build-up can encourage dust build-up
- Dust extractors are impractical for fine dust control
- Can be costly to run
Workshop vs Home air filtration
Workshop air filtration is not the same as you would use in the home. The primary goal is to trap the wood or other workshop created dust that is floating in the atmosphere. The home-based filter unit is aimed at filtering finer particle down to 0.3 microns or water droplet carried viruses such as Coronavirus.
Why shouldn’t I use a home air filter in the workshop?
Workshop environments produce high levels of dust and a home-based HEPA type filter is too efficient. The filter would clog within an hour and need replacing. Workshop filters need to have a very large filter area or a course filter as found in the Microclean.
I do have installed a home-based air purifier made by Levoit and it is very effective in a space up to 400m3 with its 3 stage filtration system. Although this air filter is great for the house I doubt it is suitable for the workshop.
I highly recommend installing a system in the house as I and my family can tell the difference in the air and we find our allergies are not a problem.