Aerospace Manufacturer Pivots to 3D Print Masks for COVID-19 First Responders

“We’ve seen all of these companies and home makers jump on the bandwagon of printing a mask,” says Terry Hill, owner and CEO of Rapid Application Group (RAG). “We haven’t slept in the last four or five days because we want to make sure this is correct — that the material science is good, and the design is good.” 

Hill and his team at RAG have spent those sleepless days in a whirlwind of product development to create a safe and practical 3D printed mask to protect against coronavirus. The device is intended to be used as personal protective equipment (PPE) by first responders and medical support staff. I spoke with Hill and Jason Dickman, COO, on Thursday morning, and later that afternoon the mask passed a final fit test at local clinic in Tulsa, Oklahoma.

The RAG mask is based on previous designs and consists of two plastic 3D printed components that hold an N-95 or HEPA filter, which can be cut from an existing mask or larger piece of material. A food-grade silicone tube in the lip of the mask creates a comfortable seal for the wearer. The reusable mask can be disassembled and cleaned between uses, and the filter replaced as needed. One N-95 mask could provide 4 to 6 filters for the RAG mask.  

Notably, the mask is designed not necessarily to replace N-95 masks, but to free up more of them by providing a protective alternative for other healthcare professionals.

“​Field-level or nonsurgical PPE can save lives right now, and maybe put some of those other N-95 masks and other surgically approved items into the specific areas where they are needed,” Dickman says. 

The idea to print PPE was at first an independent initiative on the part of Rapid Application Group, but the company is a member of America Makes and has worked with the VA and FDA and other partners on the RAG mask. While the emphasis currently is on field use, the company is in the process of seeking full FDA approval for use in a clinical setting. (At least one similar design submitted through the NIH 3D Print Exchange has been approved as a suitable stop-gap measure for clinical use.)

While the company intends to share the design once fully documented, Hill and Dickman both caution against 3D printing masks without due diligence. “We spent a lot of time planning to make sure we get this right,” Dickman says. “These are medical devices so you have to be careful; you can’t make any assumptions with this kind of scenario.” 

RAG, which typically serves the aerospace and defense industries, is now preparing to ramp up to print production quantities of its masks using selective laser sintering (SLS) 3D printers from 3D Systems and EOS. The printed components are made with DuraForm PA or nylon PA12; both are USP Class VI materials suitable for medical devices that can be sterilized and are autoclavable. The printed parts are unpacked and cleared of powder, and then cleaned with a dipping procedure in the company’s mechanical testing lab which has been converted into a cleaning station for this purpose.

“We’re not a full medical company, so we can’t guarantee 100% sterilization,” Hill says, “but we are trying to get them as clean as possible. That’s why we’re using the materials we are. As [the PPE] comes into the hospital, they can sterilize it.”

The SLS process requires no support structures and allows parts to be stacked in the build volume; Rapid Application Group estimates that it will be able to nest up to 120 masks in a single print. The company already has orders from a hospice clinic, the U.S. Army and a number of local healthcare providers. 

Along with masks, Rapid Application Group is also 3D printing face shield visors that can be equipped with any transparent plastic with holes made with a standard three-hole punch. The design features a locking mechanism at the temples to easily attach a shoe string or other strap.