Every time you hear experts talk about “flatten the curve” in the fight against COVID-19, what they're basically trying to avoid is overwhelming healthcare systems, which translates to a shortage of beds, respirators, surgical masks, and protective equipment for medical staff. Several companies around the world have decided to retool their production lines to meet demand, but the DIY world hasn't been asleep either, and one of the best examples comes from Johnny Lee, best known for his Wiimote hacks. Lee is back with a DIY variant of the so-called PAPR positive-pressure respirators with integrated filtration.
COVID-19 is rapidly approaching the 400,000 infected mark, the exponential growth is already evident in many countries... and resources are running short. As much as some people refuse to understand and politicians look the other way, those nearly 400,000 cases have put all healthcare systems in check, public and private alike. And the pandemic is still in progress. The number of sick will increase, and as if that weren't enough, medical staff cannot access adequate protection.
Several companies have already confirmed they will temporarily step away from their classic products to focus on producing medical equipment (for example, Razer announced it will donate a million surgical masks), but not a few wonder what the DIY world can do about it. The DIY and medicine don't have the best relationship, however, Johnny Lee's latest project (the same one from the Wiimote hacks) could be useful in an emergency.
From Ventilator to PAPR
It all started with a prototype of a respirator/ventilator that he published last March 18. The original idea was to repurpose a CPAP device (the same one used to treat sleep apnea) so it could be applied during an acute respiratory crisis. Within a few hours, he received comments from specialists (including respiratory therapists) who highlighted the limits and potential risks of his prototype. With this new information, Lee hopes to improve the overall design of his ventilator, but at the same time, he decided to explore another, safer alternative using almost the same parts.
The result is a PAPR device or low-cost positive-pressure respirator, something medical staff will likely see as more valuable during their rounds for two simple reasons: Unlike a conventional respirator/ventilator, the PAPR is a preventive device, and they are already scarce even in the best-equipped hospitals. Moreover, Lee mentions the direct impact of such a device, since a ventilator can only assist one person, but a PAPR could keep a doctor safe to cure dozens.
Components
- The CPAP machine's blower
- An NRBC air filter
- A 3D-printed adapter
- A battery for the blower
- The CPAP face mask with its tube
- Swimming goggles
- A full face shield
- A backpack that houses the electronics and keeps your hands free
The adapter connects the air filter to the blower and uses a significant amount of duct tape to create a seal. The filter doesn't necessarily have to be NRBC, since only its 'B'iological function is needed, but if it becomes very difficult to obtain, with another 3D-printed adapter it's possible to connect N95 or P100 filters. The rest is a matter of connecting all the elements, and using a small switch to modify the blower speed.
Details and Improvements
All the details have been published on GitHub, so anyone interested can explore the design and make the corresponding improvements. One example Lee cites is the position of the filter. In the video, the filter is placed 'before' the blower (since it doesn't come 100% sealed), but it would be much more convenient and safer to place it 'after'. Of course, the whole project takes a back seat if professional help and equipment are available, but if the emergency is very advanced, this could serve in the absolute absence of basic protection.
PAPR device on GitHub: Click here
Ventilator/Respirator on GitHub: Click here
https://old.neoteo.com/foldinghome-ayuda-a-derrotar-al-coronavirus-con-tu-pc/
