COVID-19 respirator
I am a physician and wish to challenge the 3D printing community to design and post respirator shields designs for front line medical workers dealing with COVID-19. What would be most useful is something that looks and works like the Trend Faceshield ( http://www.trend-uk.com/en/CA/productlist/2/1/face_shields.html ). Modifications might include modifying the filter casette to insert filters cut from readily available HEPA filter material, air circulation powered by readily available PC fan using standard batteries, a clamping mechanism at the front to hold transparent face shield sheet material that we can obtain readily from various sources. We are rapidly running out of personal protective supplies. A good design could be reproduced from local 3D printing communities...and save front line workers and lives.
RE: COVID-19 respirator
Pierre, I have been doing some research on the topic. I found that Manley ventilator from 1961 is simple enough to be built. His design operates with pneumatic pressure that can be provided by a small compressor, like those used for inflating tires. The problem is that the ventilator uses at least three valves. I think the valves can be 3d printed. You can see its description in the following link
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2044.1995.tb04517.x
RE: COVID-19 respirator
I hope some pneumatic engineer in this forum may design the valves
RE: COVID-19 respirator
It would be a great contribution.
RE: COVID-19 respirator
Do you know how to find a pneumatic engineer that may help with the valves design?
RE: COVID-19 respirator
Hi all,
a few remarks from the sideline before too much energy is wasted her. I am not yet working in the front line, but as an intensivist in NZ I have spent a considerable amount of time in preparing for the surge that hopefully never comes.
In extensive discussions within our team we have actively decided against the drop down from the forehead visors and we opted for a combination of protective glasses and an upwards facing shield.
rationale:
- downward facing shield needs to be quite far away from your face to allow for any head down movement
- if the shield is short enough to allow appropriate movement it will be too short
- if the shield is longer it needs to be far away from the face generating a huge gap around the neck
- in a common ward/ICU setting the patient will be below the level of the healthcare worker, with the downward shield this will expose the open area of the shield to spray from aerosol generation by the patient (intubation/braking the ventilator circuit/leakage/coughing/sneezing)
So if any design effort goes into such a project the starting point should rather be a "don't scratch" collar/funnel for pets than something worn on the forehead.
Unfortunately I am currently too busy to design anything, but would be happy to chip in more stupid ideas and potentially helpful comments during breaks from other work.
Stay safe, stay away from each other, stay home if you can!
Hansjoerg
RE: COVID-19 respirator
just as an afterthought, the basis of such a design could be a helmet for non invasive ventilation, downside is, that it would need quite a large amount of airflow, wouldn't need the top valve attachment, air inlet and outlet in the bottom ring construction, to avoid the need for valves a constant flow design would simplify things even more
would most likely be rather noisy, so not necessary something you would want to wear for a whole shift, but could be a starting point for something that could be easily put on when a person has to enter an isolation area in a hurry
RE: COVID-19 respirator
Tested with ETCo2 and Sat monitoring, and wearing for hours. Also passed saccharine nebulizer airborne isolation test.
Now online. Build instructions to follow
https://www.thingiverse.com/thing:4243272
RE: COVID-19 respirator
Awesome stuff, Guy. Please advise if there are practical prints we can be doing for the COVID front liners. Everything I'm reading from authoritative sources seems to be indicating that respirators are a waste of time. Shields are promising but require extra parts. I've seen suggestions that things like disposable no-touch thermometer covers might be useful. After days of looking about, I'm not finding any place that would accept anything I can print on a consumer-grade FFF printer.
RE: COVID-19 respirator
I agree that producing prints that will be actually used serious protection is difficult. Institutions will not readily accept unregulated protective gear. So, push from the non-medical side is resisted.
However, we who are the actual boots on the ground have an unfulfilled demand and things like this get deployed "around" institutional official sanction.
This is an opportunity to provide actually functional protection that is near equivalent protection level. I'm actively pushing the design out to the medical community to develop awareness of the possibility for more PAPR's. Once, we get some requests, then we can start printing up the halos and its fittings.