[IR + Misc.] Covid-19 Discussion and Birna's C-19 Photo-Collage

[Andy Perrin]

David, it IS about getting it wet. If you don’t use a thick enough coat of alcohol it dries out almost instantly. Yet the directions you can read directly above where Andrea pasted them say bleach solution needs as much as 10-60 minutes!

[dabateman]

David, it IS about getting it wet. If you don’t use a thick enough coat of alcohol it dries out almost instantly. Yet the directions you can read directly above where Andrea pasted them say bleach solution needs as much as 10-60 minutes!

 

It all depends on what you are trying to kill. Bacterial Spores are really tough. Bacillus stearothermophilus spores are used to validate autoclaves as its hard to kill them. Not using enough moist heat in an autoclave and they will survive.

 

I haven't seen any validation data for corona virus yet. So not sure how tough it is to dry out. But it does need moisture to cause human infection, just like SARS did back in the Toronto scare.

[enricosavazzi]

On the theme of UV desinfection and Coronavirus:

 

https://www.bbc.com/...siness-51914722

 

The xenon tubes used in these machines seem to be giant (meter-long) versions of xenon flash tubes. Hopefully none of our most adventurous members will use one of these machines for self-experimenting its effects on human skin.

 

Edit - Next, we might hear of world-wide xenon shortages caused by high demand for these machines.

[enricosavazzi]

[...]

I haven't seen any validation data for corona virus yet. So not sure how tough it is to dry out. But it does need moisture to cause human infection, just like SARS did back in the Toronto scare.

 

A study on viability of HCoV-19 after variable time (hours to days) on various types of surfaces. This study is also referred to on the NIH web site, and therefore likely to be reliable. Not a direct answer, but it does not seem to exclude the possibility of infection by touching a contaminated surface. I had to look up this information to answer an informal inquiry on the possibility of contagion by touching common items available in a typical public library. While cardboard (and presumably paper) is unlikely to cause infection after a few hours, plastic is more likely to be an infection source (e.g., frequently handled items like plastic-covered book covers, DVD boxes and DVD disks).

 

https://www.medrxiv.org/content/10.1101/2020.03.09.20033217v2.full.pdf

[dabateman]

On the theme of UV desinfection and Coronavirus:

 

https://www.bbc.com/...siness-51914722

 

The xenon tubes used in these machines seem to be giant (meter-long) versions of xenon flash tubes. Hopefully none of our most adventurous members will use one of these machines for self-experimenting its effects on human skin.

 

Edit - Next, we might hear of world-wide xenon shortages caused by high demand for these machines.

 

Article doesn't say Xeon, but:.

"American firm Xenex has LightStrike..."

 

It most likely is a mercury 254nm lamp. I have seen similar devices used to disinfect buses and airplanes.

 

[enricosavazzi]

There was an earlier article (maybe last year) on BBC World showing similar hospital disinfection machines that used xenon flash (perhaps the Xenex ones). I just assumed that the ones in the current article are similar, but they might be mercury arc tubes as you say.

 

Added: see

Their xenon flash tubes are much smaller, albeit still bigger than any studio strobe I have ever seen.

[Cadmium]

Stay safe, wear a mask.

[Cadmium]

Cheer up, so far no one is hoarding cakes!

[dabateman]

 

 

A study on viability of HCoV-19 after variable time (hours to days) on various types of surfaces. This study is also referred to on the NIH web site, and therefore likely to be reliable. Not a direct answer, but it does not seem to exclude the possibility of infection by touching a contaminated surface. I had to look up this information to answer an informal inquiry on the possibility of contagion by touching common items available in a typical public library. While cardboard (and presumably paper) is unlikely to cause infection after a few hours, plastic is more likely to be an infection source (e.g., frequently handled items like plastic-covered book covers, DVD boxes and DVD disks).

 

https://www.medrxiv.org/content/10.1101/2020.03.09.20033217v2.full.pdf

 

This is good. But please don't use the times as hard fast numbers.

Here in Washington DC area I worry for summer. You walk out of an air conditioned building outside and the heat and humidity is so hogh that your face will become wet. Sometimes your clothes will look like you took a shower.

 

In the south west USA, you need to eat your ice cream fast as it will sublimate ( from ice to gas) right off the cone. Due to the dry heat. So remember not all places are the surfaces equal.

 

Studies will typically use 20-25C with 60% humidity, to represent comfy human living conditions.

 

[Andy Perrin]

In the south west USA, you need to eat your ice cream fast as it will sublimate ( from ice to gas) right off the cone. Due to the dry heat. So remember not all places are the surfaces equal.

 

That is impossible. You have to lower the pressure quite a bit to get sublimation in real time (which is how they make astronaut ice cream).

[dabateman]

Stay safe, wear a mask.

 

 

This is an excellent write up and I personally (my opinion, not supported by any place I may work) agree with what is mentioned about masks and gloves.

 

https://wordpress.lensrentals.com/blog/2020/03/how-to-disinfect-camera-equipment-and-spaces/

 

[Andrea B.]

Anyone who ever wears a housewife hat (something that is *not* necessarily a female thing!) is aware that wearing protective gloves prevents "stuff" from getting into those little cuts, scratches and abrasions that we tend to accumulate on our hands if we ever work work with our hands either outdoors or indoors. "Stuff" can be harsh or drying chemicals (soaps, vinegar, alcohols) or can be bacteria/virus.

 

As for masks, goggles and other face protection during a pandemic, I'm completely baffled as to why there seems to be no recognition that masks/goggles help prevent the contact of hands-to-mucous-membranes. Masks are not a perfect aerosol barrier, we all get that. But they sure as heck help prevent you from touching your face.

Well, masks/goggles help prevent *me* from touching my face. As always, YMMV.

 

I'm perfectly willing to friendly-debate my proposition that we wear this stuff to help prevent touching face or having contamination through small cuts/scratches in addition to some small protection it might offer as an aerosol barrier.

[Andrea B.]

P. S. David, I'm laughing about the ice cream thing! I recognized your wry little joking tone.

Last night I snarfed a dish of Cow Belle Black Cherry Chocolate Chunk ice cream here in the kitchen/family area which is currently sporting a 4% humidity level. Yes, that's correct -- 4% humidity. (I go through hand lotion and face lotion by the gallons!) Anyway, the ice cream behaved quite normally. No gaseous emanations or "steam" rising from the surface. Good stuff, that Cow Belle brand.

[Stefano]

Probably I’m paying more attention than before, but I hear more ambulances than usual. Every time I hear one I think about the coronavirus...

 

How is the situation going in Australia? You had the bushfires emergency not long ago. I hope that it isn’t an emergency anymore.

[Stefano]

Today I maybe heard something like 20+ ambulances... we surpassed 4000 deaths, this is getting really scary...

 

We are reaching 500 deaths per day, the previous days we were at about 450. The numbers are still growing, we didn't reach the peak yet. Our biggest mistake was how ENORMOUSLY we underestimated the situation, it literally exploded. I hope I remain healthy in this months, because if I get something as "little" as an appendicitis, hospitals are FULL. And getting an appendicitis at my age isn't that unlikely, I have a classmate that had it last year. If someone gets sick, has an heart attack, a car crash or whatever you can imagine, there is the possibility that he/she will not receive any medical attention.

 

Edit: we had 627 deaths in the last 24 hours. That's the highest number so far.

[Stefano]

This year is going to be one of the worst in recent times. It began with the USA-Iran situation (I don't want to be political here), then the bushfires in Australia and now the Coronavirus. Let's hope for a way better 2021.

[enricosavazzi]

According to the Swedish state news today, roughly half of the Covid-19 patients that required hospitalization so far in Sweden are below 65 years of age. Comparable data is reported by some US news channels for the American population. This seems to contradict the often-stated assertion that people above 65 or 70 years are the main risk group.

[Stefano]

The statement about the main risk group is probably true, but if a country doesn't have a very "old" population you will have less cases in the elderly and more in young people. Italy is well-known to have a lot of elder people in proportion to the total population.

[Cadmium]

I have heard they use UV lights to disinfect trains in Moscow, etc.. Which I believe was being used prior to the virus.

What exact nm of UV works for the Coronavirus, I can't say, certainly UVC, but I have heard it requires very low UVC, which I am not sure most UVC sources emit.

https://www.newsmax.com/us/coronavirus-china-uv-light/2020/03/18/id/958931/

[dabateman]

I heard about 30% of USA case are between 18 and 45. So yes this is a problem.

Children are now also becoming severely affected. Below the age of 5, seems to be an issue.

 

Andrea, got my wit. Sorry Andy I was trying to add a little humor with the ice cream comment. But DC is that wet snd it does worry me. A couple times my back has been soaked wet, going from inside to outside in the summer.

 

[Cadmium]

Regardless of all the shut downs, you still have to shop for food. Doing any such things wearing a mask will protect you 10x more than walking around without wearing a mask in such a public place.

[dabateman]

My problem with gloves is the people that I have seen wear them are not taking proper precautions. I still see them touching their face. If gloves help you imagine your hands are covered in dog poop and you shouldn't touch your mouth, then great. But gloves aren't magical barriers that make you safe. They are easier to alcohol and keep clean outside, though.

 

Gloves are typically worn for 2 reasons. 1. You don't want to add your nasty dirty oilys from your hands onto something. I wear gloves when taking apart lenses as I have oilly skin.

2. You don't want your skin to absorb something toxic like too much bleach or dangerous solvents.

As far as I know the SARS-2 virus does not absorb through your skin.

 

So please wash your hands BEFORE and after you use the bathroom. Wash your hands before you eat, touch your eyes, pick your noise or brush your teeth.

 

Practice a hand washing validation. Get some oil, ideally motor oil. But olive oil may work too. Coat your fingers and all over your hands.

Now wash your hands using what you would normally do. Did you get all the oil off? If not, you need to wash your hands until its off, and remember how you did that. Now every time you wash your hands follow that exact protocol.

 

 

[Cadmium]

I know and see a lot of people who wear gloves, but no mask. I shake my head.

https://www.nytimes.com/2020/03/17/opinion/coronavirus-face-masks.html

[dabateman]

For a mask to be useful you have to fit test it. You can see some examples here:

 

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9780&p_table=STANDARDS

 

You need to shave immediately before wearing a mask and you still need to be cautious when wearing a mask. The filters need to be changed and not touched depending on the type you use.

Practice distance, stay 6 feet away or more from people and use only self check outs if possible.

 

A mask can harm you if it causes you to breathe harder and leaks. When I worked at 3M fit testing was slightly harder than you may think and some people never passed.

 

I just stay away from people. If I needed to take an elevator, a subway, a train, a plane or be stuck in a closed space, then yes I would wear one of my N95 masks.

 

However, order stuff to be delivered if possible. Stay at least 6 feet away from people. Stay in open spaces.

[Stefano]

Stay at home if possible. Go outside only if necessary.