3D printed respiratory masks with replaceable filter

What is the need?

Currently the supply situation for professional respiratory masks is very tight. In particular, nurses, doctors and emergency medical services are relying heavily on virus-proof masks of the types FFP2 and FFP3.

How was the problem solved?

The researchers at Fraunhofer Plastics Technology Center Oberlausitz (FKO) in Zittau have developed and manufactured a reusable respiratory mask by applying a selective laser sintering process using polyamide. Currently approx. 150 to 200 masks can be produced per week. In order to realize a higher number of pieces, the Fraunhofer scientists are investigating the production of respiratory masks by injection molding.

What is available now?

Additively manufactured respiratory masks are available, including a replaceable filter. These masks are skin-friendly, resistant against disinfectants, and, above all, they can be reused. In contrast to the common FFP single-use masks, only the filter fleece is replaced (cost: less than 5 cents per filter). An exhalation valve is integrated into the mask, which prevents the filter from being soaked quickly by the respiratory air, which in turn would decrease its effect. The fleece has the same filtration effect for small particles (< 0.3 µm) as FFP3 facepiece respirators.

Where and how can the solution be applied?

The 3D printed respiratory masks are tested for their practical suitability in the Zittau hospital and by the nursing service Johanniter in Zittau, and are later used, if necessary. The regional association of fire departments has also shown interest in these masks. Particularly, the objective consists of meeting the need in the tri-border-region of Germany, the Czech Republic and Poland. The respiratory masks can be used wherever medically necessary.

Currently these newly developed respiratory masks are not certified medical products. 

Who has supported this development as a partner?

• Developer of the filter fleece: Sächsisches Textilforschungsinstitut STFI Chemnitz [Saxon Textile Research Institute of Chemnitz]

Who is the contact person?

If you have any further questions, Prof. Dr. Sebastian Scholz will be happy to answer them.