The corona virus outbreak caused a shortage of facemasks. Medical staff work in perilous circumstances when they don’t have access to the protective equipment necessary to care for patients while staying safe themselves. We encourage everyone who can contribute to make such masks for personal use to do so. But for high protection masks the whole world is searching for material. The market is showing the worst excessive and unethical behaviour. How can we make a mask that is hybrid and flexible enough to adjust to resources available we we can step out the war on materials without losing quality of protection for everyone.

We want to offer an open available model for making different types of masks depending on the need, context and available materials.

3D printed masks with different kinds of replaceable filter have the advantage that they use less of the valuable material required to protect from the virus. Moreover, many people around the world have access to 3D printers which allows them to produce locally and on-demand. 3D printing goes technically slower than mass production, but at this moment, we need a solution that can be implemented today! The same design can be used for faster production technics as soon as the production units are there and the material available.

A lot of makers all over the world are making masks. We join them and apply their findings to a local context and share our knowledge, so others can do the same. We specialised in filtering over the last 4 weeks and have found 4 to 5 different possible and safe materials that can be used. We adjusted the disposable filters so you can use one of the types depending on local availability.

Requirements

Fitting

The mask should fit around mouth and nose without letting air through anywhere but through the filter. Think about the shape of the mask, the materials (flexibility) and how to adjust the straps for different sizes.

No air leaks: no face seal leakage, exhalation leakage and filter penetration.

Look at techniques used in plumbing and pneumatic systems.

Comfort

Both ergonomically (shape, size, weight…) and easy breathability.

Condensation from breathing may be a hindering factor. Replaceable filter: the filter must be easily replaced. Several filter materials can have a thickness up to 1 cm or even more. A closed compartment is necessary for these types. Make sure visibility is acceptable and comfort is garanteed.

Production

Try to minimize the time it takes to print parts, preferably by reducing the size and material types to a minimum. However, keep in mind lower quality and density prints may compromise safety and hygiene.

Materials

In a prototyping phase, the mechanical properties (flexibility) that suit the requirements above are most relevant. Filament printing can be used, but be aware this is only a prototype.
For medical use, materials must be able to withstand 135°C temperatures to disinfect equipment. MJM printing is required.

Materials that may come into contact with the wearer’s skin should not cause irritation or present any other adverse effects to health.

Highly flammable materials should be avoided.

We are working hard on an outline of the requirement for filters. But we can use all the help possible.

This is what we are looking for:

Merv13 – MPR 1500-1900 – FPR 10
Multi-layers filters are the next step to explore and will effect the design. So stay tuned.

Principles for contributions

To make the design adjustable for different types of filter materials, we recommend working with easily adaptable parameters. Thickness but also shape may vary (some materials can’t be cut with curves).

To collaborate efficiently, we communicate through a group in Slack: join the group JOGL Covid-19 and subscribe to the #proj-mask-team channel and share files on shared drive. We suggest you use the following naming system: ADAM_V1 or ADAM_V2_YYYYMMDD_ yourname.

To ensure the design can be easily spread amongst makers and designers, we work with an open source model. Make sure you use the name as specified above to show you agree with this principle. By using the name ADAM_V1 or ADAM_V2, you agree with the Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0), so all use based on your design will be open and shareable.