Wear masks in shops

[platinumsage]

Ditto, anyone who objects to someone suggesting a method of killing the coronavirus.
You didn't even read what I'd written. You just needed people to hear your bluster. Are you even aware of far-UVC? Here, I'll save you the trouble of googling it... Type of UV Light Called Far-UVC is Safe to Use Around People and Kills >99.9% of Airborne Coronaviruses: Study

If and when I'd posted information on how to build what I built, I would have also posted any necessary warnings.

That study is about killing airborne virus. Inactivating virus in tiny airborne droplets moving around in the air bears no relation to disinfecting packaging where the virus has been deposited by e.g. someone coughing on their hands and smearing it on the surface.

But yeah as you’re an engineer don’t let me stop you having fun with your special box.

 

[platinumsage]

I asked.
And I know about the dangers of UVC. I also know Saul Goodman is an engineer and would know what he is talking about. So I asked because I wanted information on how to use them etc.
I do know that UVC is highly dangerous but isnt it used in hairdressers every day to sterilise brushes and scissors?
Possibly not at a wave length strong enough to kill off covid19 but still...I was asking for info. And that's what threads like this and members here are good at sharing.

I said wiping is safer and far more effective, sorry if that isn’t useful information to you, but perhaps it will be to other people reading this and contemplating buying some UV bulbs from ebay.

 

[Aladdin]

I said wiping is safer and far more effective, sorry if that isn’t useful information to you, but perhaps it will be to other people reading this and contemplating buying some UV bulbs from ebay.

I know about wiping and sanitising. I do it all the time.
I was asking about the UVC system because I wanted to look at ways to keep masks sanitised without washing them all the time. I have 3 very good FFP3 masks but they cant be washed. I thought a UVC box might actually sanitise them.

 

[Saul Goodman]

That study is about killing airborne virus. Inactivating virus in tiny airborne droplets moving around in the air bears no relation to disinfecting packaging where the virus has been deposited by e.g. someone coughing on their hands and smearing it on the surface.

But yeah as you’re an engineer don’t let me stop you having fun with your special box.

I know exactly what the study is. It's being studied to determine whether UVC lights can be used in public spaces to kill the virus before it even reaches surfaces. That doesn't mean it isn't effective on surfaces. It just means that your assertion that...

The kind of UVC lamp needed to have a good chance of efficiently killing cornavirus would also be far more dangerous to the skin than UVA or UVB lamps

Should be taken with a large pinch of salt.

Anyone who wishes to read up on the efficacy of different types of UV light on viruses is free to do so. It's only a Google away, but I'll continue to use mine, especially on things like apples, which people may have handled in the shop, and aren't really suitable for washing with denatured alcohol.

 

[platinumsage]

I know about wiping and sanitising. I do it all the time.
I was asking about the UVC system because I wanted to look at ways to keep masks sanitised without washing them all the time. I have 3 very good FFP3 masks but they cant be washed. I thought a UVC box might actually sanitise them.

Nothing has been published using the actual virus yet, but this paper looked at other contaminants and the answer is basically no, not with something you make at home.
Their "high-level" kit was more effective but that does stuff like "1 minute of fogging, 5 minutes of dwell time, and 15 minutes of scrubbing and dehumidification during which peracetic acid, hydrogen peroxide, and acetic acid were removed by passing through activated charcoal filters"

edited to add: forgot link Effectiveness of Ultraviolet-C Light and a High-Level Disinfection Cabinet for Decontamination of N95 Respirators - PubMed

 

[platinumsage]

I know exactly what the study is. It's being studied to determine whether UVC lights can be used in public spaces to kill the virus before it even reaches surfaces. That doesn't mean it isn't effective on surfaces. It just means that your assertion that...

Should be taken with a large pinch of salt.

Anyone who wishes to read up on the efficacy of different types of UV light on viruses is free to do so. It's only a Google away, but I'll continue to use mine, especially on things like apples, which people may have handled in the shop, and aren't really suitable for washing with denatured alcohol.

Virus in tiny circulating droplets is obviously much more amenable to deactivation by UV light (especially 220nm UVC) than virus sitting in a slime on a surface. This is basic biology.

Wash apples with soapy water.

 

[CNT36]

Masks should be encouraged though people should be educated about them and not sold fantasies about them having been a magic bullet in places like South Korea. Masks protect people from you more than they protect you. A great reason to wear them in my book. You can think about it a little like vaccines. By wearing one you're protecting everyone especially those who cannot. The news today seems to have cottoned on to masks providing a false sense of security. This is important to emphasise. Don't act like a thin piece of fabric makes you invincible or you could increase rather than decrease your chance of infection.

 

[Aladdin]

I'll continue to use mine, especially on things like apples, which people may have handled in the shop, and aren't really suitable for washing with denatured alcohol.

One could wash apples down with this perhaps?


95% alcohol free

Bruichladdich X4 Quadrupled Whiskey (92% Alcohol)

"Hands down, this is the most alcoholic single malt whiskey that is made using a 17th century quadruple distillation method. It is known to be extremely potent and pure. According to legend, Martin Martin, a Hebridean traveler was told by the locals- 'one sip and you live forever; two sips and you go blind; three sips and you expire on the spot.'

 

[weltweit]

Indeed the covid-19 virus is tiny someone said you could fit 300 million of them on the head of a pin.

So it takes quite a mask to prevent them getting in. But your wearing a mask does prevent you exhaling droplets into the wider environment.

Wearing a mask should be come an issue of politeness.

 

[Yu_Gi_Oh]

Masks should be encouraged though people should be educated about them and not sold fantasies about them having been a magic bullet in places like South Korea.

Well since everyone in South Korea was wearing a KF95 mask, I don't think we can really hope for similar with a thin bit of fabric anyway.

 

[CNT36]

Indeed the covid-19 virus is tiny someone said you could fit 300 million of them on the head of a pin.

So it takes quite a mask to prevent them getting in. But your wearing a mask does prevent you exhaling droplets into the wider environment.

Wearing a mask should be come an issue of politeness.

Also prevents droplets coming in to some extent. Last I looked into it this virus usually only travelled through the air in relatively large droplets (so short range) rather than on its own.

 

[Saul Goodman]

Virus in tiny circulating droplets is obviously much more amenable to deactivation by UV light (especially 220nm UVC) than virus sitting in a slime on a surface. This is basic biology.

Wash apples with soapy water.

And basic mathematics can be used to calculate the time required to render the virus ineffective. It's a simple inverse square calculation, based on light intensity and distance. I'm sure Google can probably find a calculator for the job, but lower light intensity just means longer exposure to achieve the same result, and the ozone created by the lamps facilitates the process.

So yeah, I'll continue to use my "special box", because I don't live in an either/or world.

 

[CNT36]

Well since everyone in South Korea was wearing a KF95 mask, I don't think we can really hope for similar with a thin bit of fabric anyway.

No, but they also had a lot of other things going for them like a decent Tetris (eta Test, trace and isolate) system.

 

[Yu_Gi_Oh]

No, but they also had a lot of other things going for them like a decent Tetris system.

What they had, fundamentally, was a desire to get as close to eradicating the virus as possible, and a sense of responsibility to their citizens, neither of which our government has. This was expressed in numerous ways, such as the availability of proper masks, their testing and tracing, their clear communication, their provision of other PPE like hand sanitizer, and their ability to make a fucking plan and carry it out.

 

[platinumsage]

Indeed the covid-19 virus is tiny someone said you could fit 300 million of them on the head of a pin.

So it takes quite a mask to prevent them getting in. But your wearing a mask does prevent you exhaling droplets into the wider environment.

Wearing a mask should be come an issue of politeness.

People aren't typically infected through inhaling individual virus particles - transmission is mostly via droplets, so a mask will protect you to some extent if the mask is capable of stopping droplets.

 

[platinumsage]

And basic mathematics can be used to calculate the time required to render the virus ineffective. It's a simple inverse square calculation, based on light intensity and distance. I'm sure Google can probably find a calculator for the job, but lower light intensity just means longer exposure to achieve the same result, and the ozone created by the lamps facilitates the process.

So yeah, I'll continue to use my "special box", because I don't live in an either/or world.

Absolute rubbish I'm afraid. Biology is far more messy than that

 

[Saul Goodman]

Absolute rubbish I'm afraid. Biology is far more messy than that

UV-C Light Kills SARS-CoV-2, Triggering Novel Lighting Options for Public Spaces

UV-C light has been used as a disinfectant against viruses and bacteria for more than 40 years. Now, researchers at Boston University and Signify (formerly Phillips) have confirmed that it also effectively eradicates the SARS-CoV-2 virus.

www.biospace.com

Specifically, a 5mJ/cm2 dose of UV-C light eradicated 99% of the SARS-CoV-2 virus in 6 seconds, according to testing by Anthony Griffiths, Ph.D., associate professor of microbiology, in Boston University’s National Emerging Infectious Diseases Laboratories (NEIDL). Based on the data, he and his team determined that a 22mJ/cm2 dose of UV-C light will result in a reduction of 99.9999% of the virus in 25 seconds. That translates, at a basic level, to needing a 13W UV-C light bulb to kill viruses in a 10 x 16 foot (15 square meter) room,

I'm using 2x 60W 254nm lamps, in an area less than 1m2

Also, Far-UVC has been tested and is effective on surfaces.

Again, I'll continue to use my "special box", not because you talk a lot of bollocks, but because I did a lot of research before building it, and I rarely invest time and money into something that isn't going to work.

 

[nyxx]

Also prevents droplets coming in to some extent. Last I looked into it this virus usually only travelled through the air in relatively large droplets (so short range) rather than on its own.

The WHO recently acknowledged that this virus is transmitted by aerosols as well as in droplets.

 

[platinumsage]

UV-C Light Kills SARS-CoV-2, Triggering Novel Lighting Options for Public Spaces

UV-C light has been used as a disinfectant against viruses and bacteria for more than 40 years. Now, researchers at Boston University and Signify (formerly Phillips) have confirmed that it also effectively eradicates the SARS-CoV-2 virus.

www.biospace.com

I'm using 2x 60W 254nm lamps, in an area less than 1m2

Also, Far-UVC has been tested and is effective on surfaces.

Again, I'll continue to use my "special box", not because you talk a lot of bollocks, but because I did a lot of research before building it, and I rarely invest time and money into something that isn't going to work.

I can't see that Griffiths has published that research, so we can't see what surfaces and virus preparations he used.

Most studies use simple deposition of virus-containing droplets on plastic or something. This doesn't allow you draw conclusions about the real world e.g. virus in a lump of phlegm absorbed into a strawberry. If egg white is a reasonable approximation to sneeze-juice, this shows just how much you have to take penetration of different substrates into account: UV PENETRATION DEPTH IN LIQUID EGG WHITE AND LIQUID WHOLE EGG

No one has published anything like this with SARS-CoV-2 yet , but when studies have been done on other viruses deposited on the surface of plants and the virus is mixed with other organic matter, the results are highly variable.

 

[Cloo]

God, just had to say to people on Twitter that, however strongly they feel, please can they not use Nazi/Holocaust analogies about social pressure/goverment rulings on wearing masks.

 

[Saul Goodman]

I know about wiping and sanitising. I do it all the time.
I was asking about the UVC system because I wanted to look at ways to keep masks sanitised without washing them all the time. I have 3 very good FFP3 masks but they cant be washed. I thought a UVC box might actually sanitise them.

This is the box I made. I've made a few modifications since, like a perspex window in the front, lined it with foil for reflectivity, and connected it to a HEPA filtration system, but I'm using it for purposes other than cleaning apples

There are lots of tests being carried out on the efficacy of Ozone and UV/Ozone combinations for sterilising N95 masks and CPAP equipment, and the results are promising. E.g. https://www.medrxiv.org/content/10.1101/2020.05.28.20097402v1.full.pdf
... but I wouldn't endorse it,

For anyone thinking of building anything similar, please remember that UV light is very bad. Treat it like a wasp. Don't let it near your skin or eyes. Plastics make excellent UV blockers.
High concentrations of Ozone are also bad for you, so ensure good ventilation during use, and before you use any power tools, be sure to ask a responsible adult.
There's also electricity involved. Electricity is bad.
Probably best to just not even think about doing anything like this.

 

[LDC]

God, just had to say to people on Twitter that, however strongly they feel, please can they not use Nazi/Holocaust analogies about social pressure/goverment rulings on wearing masks.

Cloo who the fuck do you follow on Twitter? Is that friends, or Twitter 'personalities'?

 

[Marty1]

This is the box I made. I've made a few modifications since, like a perspex window in the front, lined it with foil for reflectivity, and connected it to a HEPA filtration system, but I'm using it for purposes other than cleaning apples

There are lots of tests being carried out on the efficacy of Ozone and UV/Ozone combinations for sterilising N95 masks and CPAP equipment, and the results are promising. E.g. https://www.medrxiv.org/content/10.1101/2020.05.28.20097402v1.full.pdf
... but I wouldn't endorse it,

For anyone thinking of building anything similar, please remember that UV light is very bad. Treat it like a wasp. Don't let it near your skin or eyes. Plastics make excellent UV blockers.
High concentrations of Ozone are also bad for you, so ensure good ventilation during use, and before you use any power tools, be sure to ask a responsible adult.
There's also electricity involved. Electricity is bad.
Probably best to just not even think about doing anything like this.

Looks like a lot of faffing-on compared to wipes.

Impressive tho

 

[scifisam]

I assume they're going to count any face covering as a mask, right? I mean there hasn't been any concerted effort to send out masks, and N95 masks genuinely are difficult for some people with breathing problems and other health issues (I know, there are all those memes saying "doctors are fine," but their masks are actually fairly thin), but such people might well be fine with something lighter. I mean, I know a bandana won't completely prevent me spreading a disease but it definitely will make some difference. And it helps make it normal to cover your face.

Sending out the message that "covering your face" is what counts the most would probably be more helpful than "wear a specific type of mask or give up." The latter is the message some people are giving out.

 

[bimble]

God, just had to say to people on Twitter that, however strongly they feel, please can they not use Nazi/Holocaust analogies about social pressure/goverment rulings on wearing masks.

Some people are just mad. Mostly trump supporters seem to be saying this? They think being inconvenienced or a little bit sweaty is the same as being brutally oppressed.

 

[CNT36]

The WHO recently acknowledged that this virus is transmitted by aerosols as well as in droplets.

Half heard something on the news but not had a chance to check it out.
Had noticed a few preprints talking about that but that droplets were much more common. Iirc there was something about some people producing a lot more aerosol than others.

 

[Marty1]

So how come posties or other delivery people like DPD, Iceland home deliveries aren’t wearing masks then?

 

[Saul Goodman]

Looks like a lot of faffing-on compared to wipes.

Impressive tho

Again, it's not an either/or thing. I wipe (the things that can be wiped) with a 70% IPA solution first, then finish the job under UV.
I made this thing for a different job, long before the virus came about, but seeing as I have it, why not use it?

 

[Cloo]

Cloo who the fuck do you follow on Twitter? Is that friends, or Twitter 'personalities'?

No, I don't follow friends - the person who said this seems generally a nice and well-meaning lady. She's been very upset by the mask thing as she and a child are on autistic spectrum and really find them unbearable to wear and I think although they carry some kind of medical letter saying they are exempt, she has said they've been harrassed for not wearing masks on public transport (I don't think she drives). So she's been very against mandatory mask wearing, even with medical exclusions, and it's sad because you can see she is anxious and upset, and now there's people replying to her posts with the whole 'It's a global conspiracy to oppress everyone' (honestly not sure how) and how everyone in a mask is judgey and sanctimonious and will report non-wearers to the authorities. and it's not really helping her. What we need, I think, is raising awareness that there are reasons for health, deafness, being non-neurotypical etc, why some people can't wear masks, so not to assume.

 

[scifisam]

So how come posties or other delivery people like DPD, Iceland home deliveries aren’t wearing masks then?

I thought you said you were before?

Some are. For the others, they're mostly outside and don't come that close to customers. Low transmission risk.