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Open Source Ventilator
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Blitzschnitzel:
@Jorgi
You could off course get a glass blower to make a glass spiral around a UVC lamp. Are there cheaper UVC resistant and transparent materials than glass made by craftsmen? It might also be a good idea to make the worlds stockpiles of military ABC filters compatible with medical use.
jogri:

--- Quote from: Blitzschnitzel on March 30, 2020, 11:34:35 am ---@Jorgi
You could off course get a glass blower to make a glass spiral around a UVC lamp. Are there cheaper UVC resistant and transparent materials than glass made by craftsmen? It might also be a good idea to make the worlds stockpiles of military ABC filters compatible with medical use.

--- End quote ---

I don't think so, and even normal glass sucks at letting UVC pass (it transmits 1-10% at most). You need fused quartz glass for that, and that stuff is rather pricey as it is more difficult to work with (higher melting point at almost 2000°C, compared to 1400°C for normal glass). If you go to UVB normal glass as well as acrylic glass kinda work, but UVB sucks at killing viruses/bacteria.
MasterBuilder:
Medtronic have released the source for the PB 560 ventilator,  :-+
https://apnews.com/Globe%20Newswire/471a4dfe92e9697ecf5e3e177803bb54

Source here, no firmware yet
http://www.medtronic.com/openventilator
pipe2null:
@Nay-sayers:  There are valid points against DIY medical equipment, but these are extreme times:

In the count-y I live in (a "county" = a small collection of towns), we have as many confirmed COVID-19 cases as all of New Zealand and Croatia combined.  And we are not even the worst hit county in my state.  And my state is an order of magnitude better off than New York.  In the past 7 days, the number of confirmed positive cases in the US has QUAD-rupled, almost QUINT-upled.  Just over the weekend, like 2 days, the number of cases increased by almost 50% of China's total cases over the entire pandemic.  And we still have problems with availability and lag time of testing.

2 days in the US = 50ish % * 3 months in China.
https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports/
(Note: There is roughly 24 hour lag time in the numbers published by W.H.O.)

No matter how fast manufacturing of ventilators and other medical devices ramp up, and no matter how fast those devices get distributed, there WILL be lag time and a period where people will die due to unavailability of equipment.  This is already true in Italy, and I think Spain as well.  If there are reproducible DIY designs, someone from the maker community can build a device within a day or two, and even if those devices are essentially single-use-disposable, that is one less body bag.  And the maker community is much larger than a single person.  Getting a patient to sign a waiver to use DIY equipment when nothing else is available, and getting medical professionals to consider the DIY equipment in the first place, is a different issue.  We need reproducible designs first, and some coordination of those efforts.

SO:  Please contribute if you are able to.  Please be critical of design ideas when appropriate to help avoid unforeseen problems.  And please do not assume that idiot politicians will set aside personal interests and reelection campaigns for the greater health and well-being of their country's citizens, in a timely manner.  I'll stop there since I do not want to devolve into a rant.


--- Quote from: MasterBuilder on March 30, 2020, 05:02:27 pm ---Medtronic have released the source for the PB 560 ventilator,  :-+
https://apnews.com/Globe%20Newswire/471a4dfe92e9697ecf5e3e177803bb54

Source here, no firmware yet
http://www.medtronic.com/openventilator


--- End quote ---
That's freakin awesome!
pipe2null:
Adding some tangible numbers for ballpark estimation.  Excerpt from the study on virus inactivation of SARS I posted earlier:
2.3. UV light treatment
Ultraviolet light (UV) treatment was performed on 2 ml aliquots of virus (volume depth = 1 cm) in 24-well plates (Corning Inc., Corning, NY). The UV light source (Spectronics Corporation, Westbury, NY) was placed above the plate, at a distance of 3 cm from the bottom of the wells containing the virus samples. At 3 cm our UVC light source (254 nm) emitted 4016 μW/cm2 (where μW = 10−6 J/s)...
3.1. Effect of radiation on the infectivity of SARS-CoV
... Exposure of virus to UVC light resulted in partial inactivation at 1 min with increasing efficiency up to 6 min (Fig. 1A), resulting in a 400-fold decrease in infectious virus. No additional inactivation was observed from 6 to 10 min. After 15 min the virus was completely inactivated to the limit of detection of the assay, which is ≤1.0 TCID50 (log10) per ml.

2.5. Heat treatment of virus
We incubated 320μl aliquots of virus in 1.5 ml polypropylene cryotubes using a heating block to achieve three different temperatures (56, 65 and 75 ◦C).
3.2. Effect of heat treatment on the infectivity of SARS-CoV...
... At 65 ◦C, most of the virus was inactivated if incubated for longer than 4 min (Fig. 2B). Again, some infectious virus could still be detected close to the limit of detection for the assay, after 20 min at 65 ◦C. While virus was incompletely inactivated at 56 and 65 ◦C even at 60 min, it was completely inactivated at 75 ◦C in 45 min (Fig. 2C). Surprisingly, at both 56 and 65 ◦C the virus was inactivated at early time points but at 60 min a small amount of virus was detected.
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