M-Class dust is considered medium risk. While this type may not pose the same long-term health risks of class H, it is still highly recommended that you protect against it. Dust class M is common in most industrial workspaces as a result of materials which can generate it. Wood and quartz-based materials are likely to be the most common cause of the spread of M-class dust. You may experience this dust class while working with any of the following:
Cement (standard or tile)
Paint (oil and latex)
M class extractors come fitted with a flow sensor and alarm that advises the user when a dust bag or system is full, or if attention is required. As this dust class is considered more hazardous, it is vital that hardware is kept running at an optimal level at all times.
Class M extractors and filters operate at 99.9% efficiency. That means there is an occupational exposure limit of 0.1mg per meter cubed.