3D printing in CoronaVirus days

Some suggestions and recommendations for 3D printing equipment for medical teams (COVID-19 Supply Chain)

Many surprises pop up and appear during the Corona Virus crisis. For example, an average scooter rider in Tel Aviv streets seems to be better protected than the medical staff in hospitals. The highest concentration of verified and blast-infected patients are high in hospitals, and while patients may no longer be able to infect each other, the medical teams treating them are in the "Ground Zero" in terms of the proximity to the viruses. They exposed to infection at any given moment. When Medical personnel, becoming infected with corona, it immediately removes him from treating patients. While the pool of potential patients is growing more and more, the medical personnel workforce is a given and final number.

Imagine, what would have happened if an airline operations center would have operated as a hospital, then an aircrew would have flown directly to New York, stopping for five minutes at the airport. Later the same crew would fly the return flight back without any rest. On the way back, the pilots would switch to autopilot, asking the flight attendant to wake them up if there was anything unusual and going to sleep. Imagine the Cockpit crew did not have any emergency equipment such as oxygen masks or rescue belts for the pilots, and if it did, then in a reduced amount, that was enough for only one pilot. The flight attendants would find it difficult to get through to the rear part of the plane because of all the passengers sitting on the floor and blocking the aisles. After four hours the plane would drop to 8,000 feet and fly without diffusion because the system was leaking, with the approach to the airport, the pilots would turn off engines and glide towards the runway because there was not enough fuel. During the holidays period, the pilots would just stay and sleep in the planes between the rounds of flights.

Many countries around the world have not yet assimilated the idea that medical personnel is not disposable and that patients’ lives depend on the availability and competence of medical personnel. Technological solutions for protecting the medical teams are known and exist; however, the quantity of equipment is insufficient and does not cover the entire medical team. Frequently, the equipment has never been tested, and the team is not well trained using it. When all countries keep their own small inventory, and import and export are almost entirely blocked, the immediate and necessary solution is turning to local production of the missing equipment, and this need for quick and domestic production is exceedingly consistent with 3D printing. Leading the trend of completing 3D printing equipment is the Maker communities and Makerspaces, which means a lot of people from different places, with goodwill, free time, enthusiasm, and access to 3D printers. This large community is willingly ready to help the medical personnel, so they have already started to download programs, design, print, and assemble the amounts of protective equipment in local production. Every day, various projects are published online, and due to the lack of protective equipment, improvised solutions have already come into use, such as the conversion of water sports equipment or homemade face masks (PPE) and face protection. Those home-based manufacturers, inspired by the Playmobil characters of children game, probably believe the medical teams should be protected and look like Bob The Builder. Medical workers are not firefighters, divers, or pest control workers, and unfortunately, the solutions of how to protect the medical teams are not supposed to be inspired by children’s games or cartoon films. If we do not want further shorten the "shelf life" of hospital workers, then it is worth considering a few essential things before pushing equipment into their hands that may endanger them and the people around them.

3D printed PPE

I encourage you to pay attention to the following highlights before you manufacture or use such improvised solutions:

A. Quality control - Home printed, machine accessory, face protection shields, or airflow connector, make me very uncomfortable for the following reasons. A home manufacturer has no control or tracking over the raw material, its components, and quality, nor does it have any control over the production and packaging process. It also cannot provide a sterilization protocol for the parts. Are the parts cleanable? What about water or air tightness testing? The entry-level manufacturing technology also cannot guarantee the same quality for every 3D part, even the same printer, and with the same parameters, not to mention printers on different websites. Think for a moment about a situation where twenty home-based manufacturers are supplying 1,000 shields to hospitals. After the delivery, it turns out that one of the suppliers detected with the Corona Virus. What can you do now? How do you know how to collect suspicious parts? What happens if one of the 3D parts found contaminated? How to find the whole series? Established companies that work according to standard and following regulatory quality control procedures use standardized work procedures and can work with adherence to health system requirements. These procedures are often written in the blood and aim to maintain public health.

a single 60 Micrometer printing layer Compared to 0.125 Mm CoronaVirus

B. Sterilization cleanses - The printed parts are designated to use in a virus-contaminated environment, so they will probably be contaminated as well. In most printing methods, the resulting plastic parts are porous material, which can serve as an excellent substrate for the adsorption of impurities and a significant challenge for cleaning and sterilization. In an efficient and organized production, the manufacturer should provide thorough information concerning the cleaning method, the shelf life of the part, and the expiry date.

C. Printing method and raw materials - The most commonly used printing method, especially in the domestic environment, is called FDM or FFF. It is also a challenging technology when used to create products for the medical environment. With this printing method, printers are being fed with plastics wire from a spool that is heated and compressed on the printer bed surface layer after layer. The two common materials used on home printers are ABS and PLA, which is considered safe and more comfortable to use. Home users use materials from unknown sources without control over the composition of the material and adapt it to the intended use. The filament deposition printing method creates a model that often does not seal for water or air tightness, meaning that the parts leak, and the layers destined quickly to be contaminated. Therefore, the attempt to make masks with N95 protection by this method is not responsible.

3D Printed Nasal Swabs

Another conventional manufacturing technology is SLA or DLP. This method uses photopolymer resin as the printing material, which is a thick liquid that becomes solid in exposure to UV light. The resulting models can be opaque and it already been used to 3D Printed Nasal Swabs. Most materials in this method were not approved for prolonged contact with the skin. In the professional field, resin with certificates used for dental medicine that will also be more tolerable for other medical uses. The parts obtained by this method are fragile, are not durable for long periods, and continue to harden with light exposure.

The most suitable production method for printing durable plastic parts is the SLS or its relative, the HP MJF. The common material ideal for manufacturing of medical products by the above methods is nylon 12, also called polyamide 12 or PA12. Some of the printer manufacturers have been approved by the US Food and Drug Administration for use in this material in medical and food applications for contact with human skin for a short time, and food containers (not alcohol). For more information on Medical Compliance - EOS, HP.

So what can be done?

3D printing is an excellent tool for developing prototype production, and tools for other manufacturing methods, such as printing a model for using flexible molds (silicone molds). When producing print parts that should be used as a final product, it is essential to thoroughly examine where and what the use of the piece is and what are the requirements for it.

Various air and oxygen pipe connectors should be tested for air pressure compliance and leakage testing at interfaces. Some professional service bureaus have people with experience and knowledge in this field. It is recommended to produce the parts only with them. Parts that come into contact with the skin should be made of approved material or coated with one. Home production in an unsupervised environment is not recommended, and in any case, all precautions should be taken when printing parts to prevent the spread of infections.

A 3D printed parts manufacturer should be able to provide proven information on the raw material source, cleaning method, and sterilization of the manufactured parts. Exterior parts are recommended to be painted with a special primer and opaque paint layer that could be sterilized with 70% alcohol.

Food and Drug Administration, the US FDA,  provides several guidelines on the issue and It also provides flexibility for crisis days.

If you have access to a Decathlon or Ocean Reef snorkel mask, and you would like to convert it to a medical oxygen mask for a patient or personnel member, please refrain from printing the necessary adaptors domestically. Ocean Reef did release the 3D files online,

Ocean Reef snorkel mask with adaptor

but because of the demand, it has begun producing the parts itself,  providing a quantity of 1,000 pieces a day, and it sends them all over the world. 

To improve the opacity of printed parts and enable
Sterilization is recommended to consider metallic coating as a complementary treatment. Polymertal is one of the companies that specialize in this type of treatment.

Gal Raz