Hazardous dusts: L-M-H

In the chemical/pharmaceutical industry working with powders is the order of the day. Handling such substances, which often pose a risk to the health of operators, requires special attention when it comes to filtration.

Solid pharmaceutical preparations, in particular tablets and capsules, are the most common of all the different types of preparation in the pharmaceutical sector. Both tablets and capsules are obtained via the handling of powders, compression for tablets and filling for capsules, producing dusts that are usually very fine and sometimes inherently dangerous.

In relation to workplace safety and the potential danger level of dusts, three classes of dusts that are considered a risk to health have been identified: L (low risk dusts), M (medium risk dusts) and H (high risk dusts). This division involves, and is also applied to, single filters as well as machines that treat and/or use hazardous substances, vacuums included.

In particular, the reference standard is CEI EN 60335-2-69, Annex AA (“Safety of household and similar electrical appliances – Part 2: Particular requirements for wet and dry vacuum cleaners, including power brush, for industrial and commercial use”). Therefore, this standard defines the maximum concentration of a substance in the air, in the workplace, that can be tolerated without having harmful effects on the health.

Nilfisk-CFM, a long-standing leader in industrial vacuum within the chemical and pharmaceutical sector, can provide both filters and machines with L or M or H certification in accordance with the above mentioned European standard. So, depending on whether L class certified machines are being used rather than M or H, the quantity of dust released on discharge will always be less, guaranteeing the highest levels of safety.

Lastly, HEPA and ULPA filters are worth a special mention. More precisely, these are filters that offer high and ultra high efficiency (High Efficiency Particulate Air and Ultra Low Particulate Air respectively, or H and U for short). All Nilfisk-CFM filters for high and ultra high efficiency, also known as absolute filters, in fact, are tested and certified individually in accordance with the strict EN 1822-1 standard (“Particulate air filters for high and ultra high efficiency (HEPA and ULPA) - Classification, performance, testing and marking”).