DUSTLESS
SANDING

M CLASS DUSTLESS SANDING

If you have ever embarked upon a DIY project such as fitting a new kitchen, bathroom or simply re-decorating, a common complaint is the amount of dust it generates. 

Even though the work may be confined to a single room, those annoying little particles seem to make their way throughout the whole house! Not only is the dust a nuisance in terms of cleaning up, it is also potentially harmful.

This is why we use market leading Mirka M Class Dustless Sanding Equipment.

Fortunately, the average homeowner only has to undertake these works every few years. But let us now think about the professional decorator who are exposed to these harmful particles every day of their working lives.

Limiting exposure to dust in the workplace is important and needs to be taken seriously.

Ignoring the fact that settled dust makes a place look untidy, there are more serious consequences to consider.

General household dust alone can trigger allergies, but dust from wood, paint and masonry can lead to serious and even life-threatening illnesses such as cancer and pulmonary fibrosis.

How does a dust extractor work?

Air pressure!

When the extractor’s motor is switched on, it turns a fan which removes air from the inside of the container sending it out into the atmosphere by an exhaust outlet, creating a low-pressure region inside.

The air outside the container is therefore at a higher atmospheric pressure which wants to move to the lower pressure region inside the extractor, taking any dust and contaminants with it.

It sounds very complicated but it’s the same principle as when you use a drinking straw in a glass of water.

Virtually all commercial dust extractors use a dust bag and cartridge filter system to trap dust and filter the incoming air. As air and dust enters the container the first filtration process is via the dust bag, this removes most of the particulates.

Any exceptionally fine particles that permeate through the bag are then filtered out by the main cartridge filter before the clean air is sent back out into the atmosphere.

This system is highly effective offering very high levels of filtration and limits the operator to re-exposure when the dust bag needs to be replaced.

Reducing the amount of dust being put into the air is always the best place to start and this can be achieved by connecting ‘on tool’ extraction, this normally means connecting to the dust extraction outlet of a power tool directly.

What is a M class dust extractor?

The three main classes of dust extraction on the UK market are L, M and H and are determined as below:

L Class – Dust that is considered Low risk such as typical household dust and soil. The filtration system needs to capture at least 99% of dust.

M Class – Dust that is considered Medium risk including; all wood dust, MDF, repair fillers, concrete, cement, plaster, materials containing quartz, latex and oil-based paints. The filtration system needs to capture at least 99.9% of dust.

H Class – Dust that is High risk ad contains carcinogens and pathogens such as asbestos and mould. The filtration system needs to capture at least 99.995% of dust.

In the UK there is a legal requirement to use the correct type of extraction equipment during any operation that generates potentially harmful dust.

The HSE issue heavy fines for any person or organisation that fails to comply. In order to explain the functions and capabilities of M Class dust Extractors, we need to be able to view them in the context of other classes of extraction.

Why use M Class Dust Extractors?

Most tradespeople will be exposed to dust from materials identified in the M category. Tasks ranging from sanding painted window frames, wall chasing, cutting worktops and floorboards all carry a risk of harmful dust inhalation requiring an M class extractor.

Indeed, the HSE set a minimum requirement of M class when using on tool extraction for controlling construction dust. https://www.hse.gov.uk/pubns/cis69.pdf

It is also important to realise that simply fitting an M-rated filter to an extractor does not make it an M class machine. Although it is essential the filter does meet the M standard the machine and components must be tested as a whole. The extractor is also required to have:

A filter bag that can be disposed of without causing risk to others – often by way of a seal which caps the entry port.

An indicator (usually an audible alarm) which alerts the user to a drop in airflow preventing the machine from working efficiently – as the case would be if the bag was full, hose blocked, or filter clogged.

Clear markings indicating its dust class.