Face mask – fast, cheap, reuseable

WARNING: The use of the supplied models is not an equivalent protection to a FFP protection mask.

WARNING: This ISM is neither tested nor certified by any offical health organisation. This ISM is an improvised fallback in case of a pandemic where surgical masks are no longer available.

A single mask set is printable in little over 1 hour.

A simple ISM has been designed, for very fast and cheap production with common FDM 3d printers. A two shell principle is applied, which are used to secure a to be selected filter media. The filter material is single use. The shells can be cleaned with soap water and are reusable.

Options for customization

Filter materials

Head strap fixture:use slotted, no slotted or clips (2x or 4x)

Scale in slicer to your needs

Style: Outer shell+Insert or 2x Outer shell

Parts are optimized for printing via vase mode of a common FDM 3D printer. This produces a single walled pieces, with wall thickness of 0.4 mm, which can be air tight.1

As these are single filament sheets cleaning is easy and effective. Soap water with subsequent rinsing is suitable for cleaning after use. Common 3D printing materials are not negatively affected by the use of soap water or other disinfectants.

Additionally, vase mode allows for very fast and material efficient prints of large volume pieces.

The improvised surgical mask consists of a large outer shell and a small insert ring to fix the filter material.

Filter material as well as selected a suitable strap are up to the user. The size of the filter material should be at least a square of 50 x 50 mm². Allowing for much reduced filter material consumption.

High quality filter materials are to be preferred: HEPA, anti microbial etc. Inform yourself of potential alternatives.

HINT: The inserts fits well after placing the filter material. If this is too loose for you. Add 1-2% to the scaling factor in your slicer

HINT: For filter material selection, check here: https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/

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ON THE EFFECTIVITY OF SURGICAL MASKS

The improvised surgical mask is intended to reduce the dispersal of aerosol of the wearer (reverse isolation). This it is not a self-protection device, its effectivity is dependent on the quality of the used filter material. The use of additional filter layers may enhance the effectivity.

For example the distribution of the corona-virus happens through aerosols. Aerosols are produced during talking, coughing and sneezing. These aerosols can come in contact with mucus membranes of contact persons. The aerosol droplets can further contact and subsequently contaminate surfaces. Direct contact with these surfaces that contain virally contaminated secretions and subsequent hand-mouth-nose contact may also lead to contraction.

The wearing of a improvised surgical mask may reduce contagion paths of the corona infection. Thus, it is sensible to wear a surgical mask for any contact with persons of the risk group to reduce the spread of aerosol droplets to the contact person.

Changelog:

UPDATE: 27.03.2020 Added a modified insert to tightly secure, when using cotton pads as filter.

UPDATE: 28.03.2020 Added a new mask model with new front clips to accompany more head strap options.

UPDATE: 02.04.2020 Added a new mask shell model, for printing without direct use of vase mode. Be aware that thorough cleanability of this model is questionable.

UPDATE: 06.04.2020 New model for serrated clips x4. Refined brim to now be flawless printable. Credit for reporting the issue goes to “turntablized”. Thank you!