Starting to print face shields. First one will be a learning piece. 2nd one should be good.
Monday, March 30, 2020
Sunday, March 29, 2020
Why I'm Not Rushing To Crank Out DIY Products - COVID-19 Entry #6
This article sums it up pretty well - Do No Harm
I'm concerned that 3D printed masks are no better than sewn fabric masks and will ultimately be more difficult to keep clean. Fabric masks can be washed with bleach, done. There's some research to support this.
I think 3dP face shields represent a better application of the tech, will help, and are far less likely to create other issues as unapproved devices.
Also, health care workers and their organizations need to feel comfortable with the product.
I've asked my wife, who is a respiratory therapist, to show some face shield designs to her people at work. If we can get acceptance for one, great. I can start making some and see where it goes. If one hospital in the Bay Area goes for it then maybe we have a project we can pull people into and scale up. We shall see.
I'm concerned that 3D printed masks are no better than sewn fabric masks and will ultimately be more difficult to keep clean. Fabric masks can be washed with bleach, done. There's some research to support this.
I think 3dP face shields represent a better application of the tech, will help, and are far less likely to create other issues as unapproved devices.
Also, health care workers and their organizations need to feel comfortable with the product.
I've asked my wife, who is a respiratory therapist, to show some face shield designs to her people at work. If we can get acceptance for one, great. I can start making some and see where it goes. If one hospital in the Bay Area goes for it then maybe we have a project we can pull people into and scale up. We shall see.
Saturday, March 28, 2020
Sterilization Techniques from a FB post - Entry #5
From the FB group Open Source COVID19 Medical Supplies - Entry #5:
EDIT: This stuff is hard! Bleach and hydrogen peroxide seem to be the best bets for DIY projects.
Hey guys, I've worked in medical device design and manufacturing for almost 20 years. I've also performed sterilization validations for many medical products. While I can't endorse any specifc methods used here, I wanted to provide some basic info and be available as a resource. I'll edit this post later to be more comprehensive
The most common methods are also probably the most out of reach to the DIY community:
Radiation sterilization (see ISO 11137)
- gamma irradiation (typically 25 kGy does the trick)
- electron beam radiation (typically 25kGy as well)
Gas exposure (see ISO 11135)
- ethylene oxide gas (this gas is very toxic so special chambers are needed)
Now for the more attainable methods:
- liquid chemical sterilization (ISO 14161)
- this is typically a peroxide of some sort but higher concentration than you can buy at the store
- moist heat sterilization aka autoclave (ISO 17665)
- dry heat sterilization aka your oven (ISO 20857)
The methods listed above are the most common but there are other 'non-traditional' methods as well.
The key to sterilization in med device is knowing your bioburden level going into the process. With this info you develop your cycle to achieve a sterilty assurance level (SAL) of 10^-6. This means an acceptable risk is that one out of a million devices sterilized might be non sterile. This limit is generally recognized by the FDA as acceptable for implants. For non implants it can be SAL 10^-3 or one in one thousand. The latter applies to things like face masks and tongue depressors and such.
UV sterilization isn't really a thing, it works on surfaces only. This is typically used in cell culture hoods with a built in bulb to keep the interior sterile but it does not give a similar assurance level as the med device sterilization methods.
I've worked primarily on implantable products which will require the above type methods. I would imagine that life saving equipment or components (like ventilator valves) would need a similar approach, but something like facemasks could be easily cleaned with surface disinfectants or UV exposure.
I am looking for any way to help so if you have questions please ask.
Kind regards, Ben
EDIT: This stuff is hard! Bleach and hydrogen peroxide seem to be the best bets for DIY projects.
Hey guys, I've worked in medical device design and manufacturing for almost 20 years. I've also performed sterilization validations for many medical products. While I can't endorse any specifc methods used here, I wanted to provide some basic info and be available as a resource. I'll edit this post later to be more comprehensive
The most common methods are also probably the most out of reach to the DIY community:
Radiation sterilization (see ISO 11137)
- gamma irradiation (typically 25 kGy does the trick)
- electron beam radiation (typically 25kGy as well)
Gas exposure (see ISO 11135)
- ethylene oxide gas (this gas is very toxic so special chambers are needed)
Now for the more attainable methods:
- liquid chemical sterilization (ISO 14161)
- this is typically a peroxide of some sort but higher concentration than you can buy at the store
- moist heat sterilization aka autoclave (ISO 17665)
- dry heat sterilization aka your oven (ISO 20857)
The methods listed above are the most common but there are other 'non-traditional' methods as well.
The key to sterilization in med device is knowing your bioburden level going into the process. With this info you develop your cycle to achieve a sterilty assurance level (SAL) of 10^-6. This means an acceptable risk is that one out of a million devices sterilized might be non sterile. This limit is generally recognized by the FDA as acceptable for implants. For non implants it can be SAL 10^-3 or one in one thousand. The latter applies to things like face masks and tongue depressors and such.
UV sterilization isn't really a thing, it works on surfaces only. This is typically used in cell culture hoods with a built in bulb to keep the interior sterile but it does not give a similar assurance level as the med device sterilization methods.
I've worked primarily on implantable products which will require the above type methods. I would imagine that life saving equipment or components (like ventilator valves) would need a similar approach, but something like facemasks could be easily cleaned with surface disinfectants or UV exposure.
I am looking for any way to help so if you have questions please ask.
Kind regards, Ben
3D Printing & DIY Links for PPE COVID entry #4
Starting a page with some links to folks working on 3D Printing & other DIY PPE projects. I'm focussing on projects that have involvement with health care professionals and/or organizations. This is as much so I have as much in one place as it is for anyone stumbling across this.
There's not much sense in doing any of these unless someone can and will actually use them in a clinical setting.
I'm trying to make some sense out of everything that's going on. Three things are clear to me:
(I'll tidy this up as I go, maybe ...)
Lowell Makes N95 Substitute & You Tube assembly video
Emergency Ventilator, I think from France
The Olson Mask & You Tube tutorial - Sewn fabric and HEPA filter media. They are asking for help in making the fabric part.
HPs Site -w- some links to some of the open source projects
GetUsPPE Maker Page
Prusa Printer Stuff:
Bacon Doctor - Mask made out of HEPA vacuum bags
How to make a mask by Deaconess health. Also seem to be trying to organize makers.
GLIA Faceshield designed by a Canadian ER worker
Big collection of projects that need to be vetted @ cults3d
Phoebe DIY Fabric Mask - with fabric recommendations and production flow suggestions
Kaiser's preferred mask how to - with fabric recommendations
John Muir Health's preferred mask instructions - with fabric recommendations
There's not much sense in doing any of these unless someone can and will actually use them in a clinical setting.
I'm trying to make some sense out of everything that's going on. Three things are clear to me:
- There are plenty of great designs out there and more on the way
- I need to find people who will use the products as they are mostly not officially sanctioned yet
- Any significant project needs space*
*I think the space issue might be solved by finding companies willing to allow a group to use it's offices. I know in the bay area there are a lot of empty eating & gathering areas right now that would be fine for 3D printing, sewing masks, light assembly, and packaging.
(I'll tidy this up as I go, maybe ...)
NIH 3dP Site With Clinically Reviewed Designs
Things people are making:
Budmen Faceshield - The one you've seen on TV the most I suspectLowell Makes N95 Substitute & You Tube assembly video
Emergency Ventilator, I think from France
The Olson Mask & You Tube tutorial - Sewn fabric and HEPA filter media. They are asking for help in making the fabric part.
HPs Site -w- some links to some of the open source projects
GetUsPPE Maker Page
Prusa Printer Stuff:
- PRUSA Printers - A bunch of uploads Some appear to be approved by some organizations
- PRUSA face shield (with brow cover) Referenced on GetUsPPE site
- PRUSA strap - 'Cause apparently people are having trouble getting elastic
Bacon Doctor - Mask made out of HEPA vacuum bags
How to make a mask by Deaconess health. Also seem to be trying to organize makers.
GLIA Faceshield designed by a Canadian ER worker
Big collection of projects that need to be vetted @ cults3d
Phoebe DIY Fabric Mask - with fabric recommendations and production flow suggestions
Kaiser's preferred mask how to - with fabric recommendations
John Muir Health's preferred mask instructions - with fabric recommendations
Projects & communities (sorta, I guess)
FormLabs project pagesStudies on DIY medical products
Mar 2020 Chinese study on effectiveness of N95 -vs- cloth surgical masks for protection agains influenza. Spoiler alert! No significant difference.
Non Woven Fabric #2 - Video -w- kinda loud music.
Non Woven Fabric #3 -Video, loud machine sounds
N95 Mask Welding #1 - Video
Right, if that stuff is making into N95s how does it get sterilized?Industrial Process References
Non Woven Fabric #1 - VideoNon Woven Fabric #2 - Video -w- kinda loud music.
Non Woven Fabric #3 -Video, loud machine sounds
N95 Mask Welding #1 - Video
Sunday, March 22, 2020
Social Distancing? COVID-19 Blog Entry #3
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| Home Depot, San Leandro, 3/22/2020 |
The trip was as much about assessing the situation at local big box retail as it was about getting things. I'm trying to plan in the face of entire systems we can no longer predict or count on. Very unsettling. We're going to need to restock at some point. I'm trying to figure out how that's going to work.
I hit two Wal*Marts, Home Depot, and Walgreens. Yesterday I tried a Target & another Walgreens. I've not tried lining up at opening which seems to be the only way I'm going to get the stuff in high demand. Really, really want to avoid that.
Today I managed to find some 71% alcohol, another bottle of hand soap, and I got some Zip Lock bags 'cause we're running low. Grabbed some Clorox foaming bleach cleaner too. There are NO paper towels or TP.
Bottled water was back in stock, by the pallet, and there was not a run on it. Food seems to be pretty much okay with a few exceptions like pasta in some stores.
Did pretty well on the social distancing. Wal*Mart was okay when I got there. People started to show up after I got there and the health care product section was getting tighter than I wanted so I left. Home Depot was nearly empty. I stopped at a Walgreens too. Again nearly empty. They had tape on the ground at the register line to help keep distancing. I was in and out of Walgreens so no issues.
That said I think it's really, really hard to strictly practice social distancing. The aisles in stores are not twelve feet wide. There's not room to line up at the registers if there's a crowd. Go to the newest stores you can. They will have more room to spread out.
Next time I go out I think it'll be time to put on the shop respirator with the P100 filters and my googles and deal with the lack of social distancing. What if someone sneezes on me? I don't know.
As for the public scoldings going on about people going out. Fair, but, we do need to get stuff. With the supply chain the way it is right now it's hard to figure out what to do. We have TP for a while, yeah. Based on what I've seen the past couple of days it's not going to be there if I let it run out. Do I wait? Do I keep trying? Amazon & other online sellers are NO help right now, at all.
Do the best you can folks. I think we're going to be in this mess until at least July.
Saturday, March 21, 2020
21-Mar-2020 JW's COVID-19 Blog Entry #2
See the entry below with links for data from various sources. As I become aware of more I'll try to update that if anyone is watching ... no promises.
I'm located in Oakland California. I've been working from home (WFH) now since a week ago yesterday, Friday. My wife is a respiratory therapist at a local 200 bed hospital & trauma center. We have adult children living with us so we are tripping over each other at this point, yeah. We are in Alameda county, one of the first six counties nationally to issue a stay at home order.
I'm located in Oakland California. I've been working from home (WFH) now since a week ago yesterday, Friday. My wife is a respiratory therapist at a local 200 bed hospital & trauma center. We have adult children living with us so we are tripping over each other at this point, yeah. We are in Alameda county, one of the first six counties nationally to issue a stay at home order.
Today's status, my version:
Well ... as of today as you may know:- Italy & EU are still seeing a lot of new cases
- UK is beginning to ramp pretty seriously
- New York city and by extension the surrounding area has become the epicenter of the U.S.; replacing Washington state, notably on the polar opposite end of the country
- Florida has finally begun to shut down the beaches
- California, New York, and Illinois have issued state wide stay at home orders
- Production in China is said to have returned to 50% - 60% of normal & trucking is returning, albeit slowly it sounds like, as local & regional travel restrictions begin to lift
- Shipping world wide is a bottle neck as passenger flights that normally also carry a lot of cargo have virtually stopped
- Agility indicates that flights are being chartered now to compensate for the lack of regularly scheduled commercial flights
- All of the data indicates people are recovering from this at a far greater pace then some are unfortunately dying
- A LOT of people are getting seriously ill and dying
- Masks and other PPE are running out, every functional ventilator is existence seems to be coming out of the wood work, industry is being asked to engage in making products they don't normally make, like vents and regulations are being eased to allow that to happen.
- The financial markets are completely screwed up. A lot of people think they are oversold. It's hard to buy in right now because every technical support point has been blown right by.
- Hopes for a "V shaped recovery" are starting to fade. Consumers are running out of money fast. The text book "marginal producers" are starting to fall off the margin into BK or worse.
Holy crap that's a lot going one at once! No wonder people are freaking out.
How long is this going to go on? (Hell if I know but here's a shot at it ... )
So what's this telling us non-science people about how long this is going to take? Let's talk about China because that's the only model we have right now.
It been about five, going on six weeks since China locked it down and it's not over. I believe the lock down began after the Chinese New Year which was on Feb 12, feel free to call me on that. Hubei province is still pretty much locked down.
China started relaxing the controls about a week ago, maybe two.
The incubation period on COVID-19 is believed to have a median I'll say of two weeks, right? So if they are going to see a second wave, it'll start end of next week or the week after.
If you look at the WHO & Johns Hopkins data they are showing a very slight increase in cases in the Western Pacific and China over the past few days. That could be noise right now.
If the cases stay flat in China for another three weeks (two weeks + another two weeks to be safe), they start to open up Hubei over the next two to three weeks after that, and they still stay flat, then, maybe we begin to have a model for the time for an entire region to recover. My little model there says that duration from shutdown to re-open would be 10 - 12 weeks.
So in the U.S. maybe we are back open for business by June 15th? Let's say July 4th for the sake of American romanticism.
Whadya think folks. July 4th?
Now then, who's got enough toilet paper, hand sanitizer, and bleach wipes to last until July 4th?
More importantly what are folks going to do who work paycheck to paycheck?
COVID-19 Links - COVID-19 Blog Entry #1
Hopefully this helps y'all out. We're getting B.S. & dumbed down information from all the media sources and our governments. They are trying to manipulate our behavior & prevent panic by shaping messages. I get it. They feel it's their jobs and some have agendas they want to push. I personally just do better with more facts.
NOTE: Even these sources can have some political spin. At least, they are one or two levels closer to what's going on.
Link to Agility's COVID-19 operational updates. Agility is a logistics coordination / facilitation / consulting company.
https://www.agility.com/en/pages/coronavirus-operational-update/
Another page of links @University Of Minnesota
http://www.cidrap.umn.edu/covid-19/maps-visuals
University Of Oxford Our World In Data COVID-19 page
https://ourworldindata.org/coronavirus
Excellent graphics
http://91-divoc.com/pages/covid-visualization/?fbclid=IwAR0340ywVbs8zPA7ftO9s0OwHYzP_HEDx0DlGAwbTnVjhmfKNdjqy24clMM
Another page of links @University Of Minnesota
http://www.cidrap.umn.edu/covid-19/maps-visuals
University Of Oxford Our World In Data COVID-19 page
https://ourworldindata.org/coronavirus
Excellent graphics
http://91-divoc.com/pages/covid-visualization/?fbclid=IwAR0340ywVbs8zPA7ftO9s0OwHYzP_HEDx0DlGAwbTnVjhmfKNdjqy24clMM
WHO Situation Reports - Daily reports with a couple of good graphics on daily case counts. Good links to other WHO resources. Daily WHO commentary on the global situation.
EU WHO Dashboard
Johns Hopkins Dashboard - In the upper right of each panel is a control that will full page the panel and return the panel back to the dashboard.
https://www.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6
Dashboard with better local representation in the U.S.
https://healthmap.org/covid-19/
Dashboard with better local representation in the U.S.
https://healthmap.org/covid-19/
Worldometer's Cornovirus Section - A few different views of the same data you're getting from other places.
NYT Charts - More U.S. oriented representations of the data.
CDC - For the sake of completeness I guess I should include the CDC site ... not impressed BTW, kinda dumbed down.
Italian Ministry of Health COVID-19 Dashboard
UK NHS Dashboard
Irish Health Service COVID-19 Page (no data as of 3/21, probably a good thing!)
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