Simple Guide for Surgical Masks Recycling in Fablabs

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Introduction: Simple Guide for Surgical Masks Recycling in Fablabs

This guide was conceived by second year bachelor students during a project around cities’ sustainability. The goal is to take profit from the abundant raw material source that masks represent, to transform them into useful and functional objects. The guide was made so that any makerspace can recycle masks in the easiest and cheapest way following our step by step procedure.

We ended up with a 4 steps process: Collection, Decontamination, Recycling, Transformation.

In our example, the final product is a plastic ruler but feel free to express your inventivity to create many other useful objects. For more inspiration, you can consult : Precious Plastic Products or Precious plastic instagram.

Supplies

1. Collect the masks

- 65cm x 30cm Cardboard

- Laser Cutter machine (optional)

- Cutter or scissors

- Cardboard box

- A4 Plastic sheet (optional)

- Computer with access to a printer

- Scotch tape or glue

-Transparent garbage bag

- 4mm plexiglass sheets (optional)

2. Decontaminate

-Rice cooker or steam machine (optional)

-Protective eyewear

-Gloves

-Face mask

3. Recycle

- Masks collected during “Collect” phase (no FFP masks or cloth masks)

- Oven (non-domestic)

- Oven tray or oven dish Baking paper

4. Transform

-Laser Cutter machine and Plexiglass sheets 4mm and 8mm (optional)

-Oven (non-domestic)

- Heat resistant silicone (resistant to at least 200°C, ex : RTV 139

-A CD shredder or hammer (anything to grind)

-Heat protectant gloves

Step 1: Mini Review of the Background

The covid pandemic has made the wearing of face masks mandatory in all public places in most countries including France. Hence, the consumption of single-use masks has increased. For instance, their production in France has increased by a factor of 20 (1) since the pandemic began and each day 4.3 billion masks made of 3.5 grams of plastics are used and thrown away in the world (2) (3). It means that we waste approximately 470 tons of plastic each day corresponding to the weight of 3/4th of Christ the Redeemer! This massive increase in consumption has also led to visible environmental issues. Indeed, they have become non-negligible waste all over the world and for example, they can now be found in the streets but also lakes, rivers, forests, and oceans (4). When they are properly thrown away, they are incinerated with non-recyclable wastes. However, face masks are made of polypropylene (5), (6), which has the big advantage of not releasing any toxic gases other than CO2 when it is heated. It can also be recycled several times (9)(10)! You can find polypropylene in numerous everyday objects like plastic tupperwares, bottle caps or even car bumpers (8). To assess whether an object is made of polypropylene, you just need to pay attention to the triangular logo. If it looks like this : ,then it is polypropylene. For more information on plastic types and recycling, you can visit :Everything to know about recycling plastic and Le recyclage du plastique : explication et conseils pratiques.

Starting from there, we wondered if we could recycle all this plastic, use it to create something else and reduce our environmental impact. In France, only a few companies have started to recycle disposable masks(10) (11). Unfortunately, no recycling procedure is free or open source. Hence, this is why we developed an open-source, easy-to-follow method to recycle single-use masks that we will detail in this guide to answer the following question: “ How can we recycle single-use face masks through a sustainable and simple process? “

We ended up with a 4 steps process: Collection, Decontamination, Recycling, Transformation. In our example, the final product is a plastic ruler but feel free to express your inventivity to create many other useful objects. For more inspiration, you can consult : Precious Plastic Products or Precious Plastic Instagram photos and videos. Although you can give your masks any shape you want, we hightly invite you to try to give them a new but also useful life. We have chosen a ruler because it is an easy object to make. We can also donate them to schools or associations for underprivileged children for exemple.

Sources :

1) La renaissance d’une filière de masques chirurgicaux en France. https://www.franceinter.fr/emissions/la-chronique...

2) Recyclage Des Masques Jetables : Tout Savoir | Recygo. https://www.recygo.fr/blog/dossier/collecte-recyc...

3) ‘Infographie. Des milliards de masques dans la nature’. Courrier international, 30 Jan. 2021, https://www.courrierinternational.com/grand-forma...

4)‘Where Did 5,500 Tonnes of Discarded Face Masks End Up?’ Greenpeace International, https://www.greenpeace.org/international/story/44...

5) Masque chirurgical en polypropylène - Tous les fabricants de matériel médical - Vidéos. https://www.medicalexpo.fr/fabricant-medical/masq...

6) Fadare, Oluniyi O., et Elvis D. Okoffo. « Covid-19 face masks: A potential source of microplastic fibers in the environment ». The Science of the Total Environment, vol. 737, octobre 2020, p. 140279. PubMed Central, doi:10.1016/j.scitotenv.2020.140279.

7) « Le polypropylène, une forme de plastique plus facilement recyclable ». Geo.fr, 14 février 2017, https://www.geo.fr/environnement/le-polypropylene...

8) « Objets cultes du quotidien - Plastics le Mag ». Nom du site, https://plastic-lemag.com/objets-cultes-du-quotid...

9) ‘Face Mask Recycling: French Firm Finds Way to Re-Use Covid Waste’. France 24, 27 Aug. 2020, https://www.france24.com/en/20200827-face-mask-re...

10) Devis pour le recyclage, la collecte et le tri des déchets de bureau en entreprise. https://www.recygo.fr/l/devis-recyclage-masques?g...

11) Collecte et recyclage des masques jetables : le grand défi !’ Solution Recyclage, http://www.solution-recyclage.fr/masques/.

Step 2: Masks’ Collection

1 - Establishment of a collective collection point.

Before being able to transform plastic into incredible objects, you need to collect disposable masks. Yours might not be enough so we advise you to establish a collective collection point which simply consists of a bin installed in a common space. Depending on your possibilities, you can install the bin in a corner of the fablab, in a public restoration place or next to already existing recycling bins.
To make our collective bin, we transformed a (45cm (length) x 35cm (width) x 30 (depth)) cardboard box. Here are the steps to create your very own bin (see figures. 1,2,3 for help):

The bin : We strongly advise you to adopt the following protocol depending on the cardboard you have. Take advantage of what you have around you! Make a simple rectangular box (45*35*30) with the top open, out of the cardboard you can find.

The lid:
If you have a bin with the same dimensions as ours, find a 80cm x 55cm piece of cardboard

  • Cut it following the model (Annex "collective bin cardboard template")
  • Cut a 4mm thick, 40cm*30cm large plexiglass sheet and cut it with the laser cutter following the given model (Annex "collective bin plexiglass template")

Finishing touches:

  • Cut a vertical rectangular hole using a cutter or scissors on the right side of the front of the cardboard box.
  • Cut the A4 sheets of plastic to the size of the hole and glue them to the inside of the cardboard box so as to cover the hole.
  • Print the pedagogical scale (Annex) and stick it on the front of the cardboard box next to the transparent window (see Photos)
  • Add the transparent garbage bag and put on the lid. Your bin is done!

/!\ We only focus on the recycling of disposable surgical face masks. FFP (2 or 3) or tissu masks must not be thrown into the collective bin as they cannot be recycled.

/!\ The top of the bin, with the opening for the masks, must be disinfected regularly.


2 - Establishment of an individual collection system.


We noticed that the majority of people throw away their disposable masks at home. To optimise the collection of the masks at a collective collection point, we suggest you distribute individual bins to those who are interested. These bins will allow each individual to collect and store their masks at home before bringing them back to the collective collection point to throw them away. This system is very similar to the one used to centralise battery collections in supermarkets.

In the annex, you will find the template (Annex "template individual bin") of the individual bin as well as a simple tutorial for folding the box (video "Tutorial folding individual bin"). It can be cut using a laser cutter machine or with scissors/a cutter.


Step 3: Decontamination Phase

The decontamination phase is an essential step of the protocol to ensure safety for those who manipulate the masks. This step is hard to develop/secure at a large scale and is one of the main reasons why mask recycling is so uncommon.

To make our decontamination protocol as safe and secure as possible, we based ourselves on a lot of scientific articles on decontamination methods to select the most secure and adapted ones to be implemented in our protocol. This decontamination phase is a two step process, later followed by the heating of the masks at 200+°C, which ensures the total decontamination of the masks.

During the whole decontamination phase, we strongly recommend that you manipulate the masks with gloves, protective eyewear and a mask. Do not forget to wash/disinfect your hands when you are finished. The masks must be collected in a single-use plastic bag inside the bin, that is to be immediately discarded after the quarantine phase.

1 - Quarantine

First of all, to considerably reduce viral infectivity, you should take the masks' garbage bag out of the bin when it is full, close the bag and let them quarantine for at least 7-10 days before opening the plastic bag again. Indeed, the studies do not agree on a precise quarantine duration to completely inactivate the virus (it can vary from 4 to 10 days, even 21) But it is shown that viral infectivity is reduced by 99,9% after 7 days,. A 99.9% infectivity reduction corresponds to a 3log10 reduction which we consider here as sufficient to manipulate the masks and put them in phase 2 of decontamination. For more information on log reduction and its significance, you can go here : https://www.sterixene.com/actualites/uv-pulses-dec...

2 - Steam cooking

7 days or more later, you can take the masks out of the bag for the second decontamination step. Finding scientific articles on steam efficiency for Covid-19 face masks decontamination. However, studies globally agree about the efficiency of steam decontamination. It is also shown that adding moisture below saturation level favor virus inactivation. Evidence is compiled in the table in Annex X.

With the two phases of decontamination combined (quarantine + moist heat), we should have a log reduction of virus activity of at least 5 => 99,999% reduction. This is sufficient to eliminate the infectious risk. To give you an idea, the total sterilization used for hospital surgical tools requires a 6 log viral reduction.

Protocol :

/!\ Wear gloves, protective eyewear and a mask at all times

  • Install your steam cooker outside or in an empty and ventilated room.
  • Put water in your steam cooker (the amount of water is different for each rice cooker depending on the brand/size)
  • Put your masks in the cooker without overpacking it (try not to handle them too much).
  • Cook for 30 minutes at the highest temperature your rice cooker allows.
  • Once finished, leave the masks in the rice cooker to cool down for 10-15 minutes.
  • Carefully remove the masks and place them on a dry surface (they may be a little wet).

Step 4: Transforming Masks Into Plastic Granules

When not melted, the fibers of masks are very solid and difficult to grind. This is why, we recommend that you first melt the masks in an oven, to get easily transformable solid plastic. To do so, nothing easier, just follow the protocol :

- Remove the elastics on both sides of each mask as well as the metallic/plastic nose wire inside it (these parts are not polypropylene).

/!\ Make sure to properly remove the attach points of the elastics on the mask, otherwise the melting product will not be homogenous (See photo ).

-Cut the masks into small pieces if you want to accelerate the melting process. -Put the masks in an oven plate with baking paper. Bake at 180°C

/!\ You can go up to 200°C to accelerate the melting process but not above as you do not want to breathe in potential toxic gases!

-The masks will melt and group together into a “liquid ball” (See Figure. 5). Wait for it to spread to form a sheet that will be easier to grind. Let the plastic sheet cool completely.

Once the plastic sheet has cooled, you can grind it into smaller pieces. This can be done using a CD shredder or a hammer.

/!\ If using a CD shredder, make sure to cut your plastic sheet into smaller pieces that can fit into the shredder. It may occur that some of the plastic can get stuck in the machine. If this happens, turn the machine off and use a pair of tweezers or pliers to try and remove the blockage. DO NOT PUT YOUR FINGERS INTO THE MACHINE.

Pro tip: Do not hesitate to grind your plastic sheet several times in order to get really small granules

Now that you have small granules of plastic, we will be able to transform them into new objects! This can be done using different techniques. We will present to you two different protocols depending on what you have at your disposition.

Step 5: Create the Object : If You Have Access to a Plastic Extrusion Machine

If you have access to a plastic extrusion machine (we used a Hollimaker), the granules will be remelted into a mold of your choice.

To make the mold, you can proceed as you wish. We decided to make a mold out of plexiglass for our ruler as it is fairly simple and can be reused multiple times. The mold is three layers of 4mm plexiglass cut with the laser cutter that are assembled together (See Figure. 8). The bottom layer has the ruler increments, the middle layer has a cut out the size of the ruler, and the top layer has a hole that will permit the injection of the plastic into the mold. The middle and top layers also have air vents that are needed to help the air escape the mold. (See Annexe for files of our mold).

Once you have your mold, here are the steps to follow to create your very own ruler:

/!\ When using an extrusion machine, always wear heat-protectant gloves

  • Place the plastic granules previously grinded in the extrusion machine. Make sure to put enough granules so as to be able to completely fill the mold.
  • Preheat the plastic in the extrusion machine for 10 minutes at 210°C.

Pro tip : While the extrusion machine is preheating, you can also preheat your mold at around 50°C (not more, to avoid the deformation of the mold) before injecting the plastic inside it. It will prevent the plasting from cooling too quickly and allows for a complete injection of long mold (more than 10 cm).

  • Hold the different layers of your mold in place using clamps. Make sure the mold is perfectly straight and well layered together
  • Place your mold under the extrusion machine so that the hole on the top layer of the mold is aligned with where the plastic will come out of the extrusion machine.
  • Once you have injected your plastic into your mold, let it cool before removing your final object from the mold.

Your object is done!

Step 6: Create Your Object : If You Have Access to an Oven

As stated earlier, if you do not have access to an extrusion machine, you can use an oven. The most efficient way is inspired from baking, you can use a silicone mold in which you will place your plastic granules and they will melt in the oven!

/!\ use a non-domestic oven, don’t use your personal cooking oven

To make the silicone mold :

We used RTV 139 silicone. However, feel free to use another type if you wish. We chose this specific silicon because it withstands high temperatures (up to 320°C).

Pro tip : make sure to choose silicon that can support temperatures at which you will melt your plastic granules.

To create your silicone mold, follow these simple steps:

  • Using cardboard, build a box for the object you wish to mold
  • Place the object in the bottom of the mold.
  • Prepare your silicone with the right dosages (usually it is written on the packaging of the silicone) and mix it well for 1-2min to make it homogeneous.
  • If you can, remove the air bubbles with a vacum chamber
  • Pour your silicone in the box over your object and let it cure for however long it needs (this information is usually written on the packaging of the silicone)
  • Remove the object carefully from the mold.

Your mold is finished!

Cooking in the mold :

/!\ For your safety and the smell of your room, please use the oven in an open and ventilated space or under a hood. Make sure to use heat protectant gloves when you are using the oven.

  • Spread your granules in your mold so as to cover the mold completely.
  • Cook it in the oven at 180 to 200°C until the granules are completely melted (it usually takes 30 min to 1 hour depending on the size of your mold)
  • When the plastic is fully melted, tap the mold repeatedly against your worktop sternly but carefully to remove any air bubbles from it (this technique is borrowed from french chocolatier)
  • Turn off and unplug your oven and let your preparation slowly cool. This step is important if you want your plastic to keep some of its flexibility.
  • Unmold your preparation, and sand it down if needed.
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