A sintered metal fiber medium as subject of the invention comprises at least a first metal fiber layer providing a first outer surface to the sintered metal fiber medium.

Further provided is a method of preparing a fibrous filter.

The invention relates also to a non-sintered metal fiber medium.

During this process, the glass fibre filter is activated by the electrostatic filter.

In particular, a fibrous filter may be placed in an upstream position within the system with one or more ionization arrays positioned downstream or to the rear of the fibrous filter in terms of airflow direction.

The metal fibers in the first metal fiber layer in the sintered metal fiber medium have a ratio of average fiber length L1 over diameter (L1 /D1) which is preferably less than 110.

The ionization array may include a plurality of electrodes each extending unidirectionally toward the fibrous filter.

It contains four types of filters in a single housing: a plasma filter, a glass fibre filter, an electrostatic filter and finally a carbon filter.

Filter plugs of the cellulose acetate fibers are water-permeable and allow discarded filtered smoking articles to rapidly degrade and expose the components to the environment.

If a glass fibre filter is used, it should be cleaned by baking for at least three hours at 400 °C.

NF EN 872 Water quality - Determination of suspended solids - Method by filtration through glass fibre filters.

NF EN 872 Water quality - Determination of suspended solids - Method by filtration through glass fibre filters.

NF EN 872 Water quality - Determination of suspended solids - Method by filtration through glass fibre filters.

NF EN 872 Water quality - Determination of suspended solids - Method by filtration through glass fibre filters.

NF EN 872 Water quality - Determination of suspended solids - Method by filtration through glass fibre filters.