So let's do an electronics project!

[turk123]

I have to say I may have too much time on my hands, but let's do an electronics project, shall we?

We have a limited amount of N95 masks that I bought a few years ago. My wife and I each have our own and we are using them up quickly. I thought of washing them or spraying them with Clorox to kill off the bugs, but then I said, "Let's nuke them".

We were using a nail hardening device until I found out the frequency of the LED light was around 350-430nm. That is just outside the range for UV light to be effective on bacteria and viruses. I needed something better.

[turk123]

After looking online for UV lighting to sterilize the bugs, I found out the wavelength we needed is 254.7 nm. Now be careful, this light is very dangerous and can cause cancer. It is also critical that you do not look at the light. It will damage your eyes permanently. Heed my warning!!!

It breaks the genes in a virus so that it cannot reproduce.

UV-C is the light we need.

[turk123]

Last warning! Do not try this at home!

I set about to build my prototype to see what it would entail. I needed a sturdy box to seal in the light (and I mean all light) and a way to hang the masks to get zapped.

I had a box that my Misfit vegetables come in and it has a 1" lining that perfectly seals out the light and the ozone produced by the bulbs. Oh, the bulbs.

I bought a unit online that is used in a furnace to sterilize bacterial as the air passes by. It has to be strong enough to do this with the very short time the air is actually in the furnace ducting. This unit has 4 bulbs and will service a 5-ton air conditioning unit. This will do fine.

Best Deal UV has the part for $139 (they also have a duel bulb for $99). The one pictured is the cheaper one, but perfectly workable.

[turk123]

Here is my prototype. Light is installed in the middle of the box and four hangers will hold the masks in an upright position.

No! I am not going to take a picture with the light on so don't ask.

I lined the box with the tin foil so you do not have to turn the masks to get the reverse side lit up. Them pixies are bouncing all around the inside of that box.

According to the literature out there it only takes about 2 seconds to literally sterilize the buggers. The bulbs are not hot, so I leave the masks in for 15 minutes. That should do it. If I turn off the lights in the room, there is absolutely no light escaping from the box. The blue LED you see in the front side of the box is just that, and LED to tell you it's on. I did not put a switch on the electrical cord to turn on the light. I wanted to force myself to unplug it when opening the box.

The bulbs also produce ozone gas that is really pronounced when you open the box. It is also a sterilizing agent and is used by the fire department to get the smoke smell out of a building after a fire. It is not something you want to breathe a lot of, so I just let the box air out on its own.

Well, that's about it.

Warning!!!! Do not ever look at this light. Will it harm you if you take a quick peak from afar, probably not. Just don't do it.

This is the same light they use in hospital surgery rooms (when everyone is out of the room!) and in city buses after they come in for the night. It has been around and used for this purpose for many years. You can buy wands that have a similar tube in them and most feel it is safe enough for consumer use. You just do not want to look at the light,

[Lafitte]

Excellent project . I have a number of N95 masks I have been reusing after 24-48 hours.

[BayouBiker]

The UV light is a cool idea, but why not just put them in the oven at 120-130 F for an hour?

[turk123]

Originally Posted by BayouBiker

The UV light is a cool idea, but why not just put them in the oven at 120-130 F for an hour?

Cause it's not as cool!

[BayouBiker]

True that!

[rmkrum]

Last I read about it, 3M did not recommend UV-C because it breaks down the material. They suggest drying in a paper bag for 7 days or use low heat as noted earlier. That’s what we’re doing.

Of course, as head of the department of overkill engineering around here, we have a full lithium battery-powered PAPR system and hood setup in stock just in case.

[mikextr]

Very cool project. Now you just need to find a way to get that UV light inside the body to kill the viruses.

[turk123]

Originally Posted by rmkrum

Last I read about it, 3M did not recommend UV-C because it breaks down the material. They suggest drying in a paper bag for 7 days or use low heat as noted earlier. That’s what we’re doing.

Of course, as head of the department of overkill engineering around here, we have a full lithium battery-powered PAPR system and hood setup in stock just in case.

The CDC has now approved the use of UV-C for sterilizing the N95 mask. There is a small degradation (possibly 1%) over time, but it is still much better than a cloth mask. The larger issue is the elastic band will deteriorate very quickly. I guess I will reduce my time to 10 seconds.

[dznf0g]

I dont think you have to run them 15 minutes. I have my late father's hearing aids and his UV sterilizer. It is a small unit that is automated to run the UV light for 8 minutes and a gentle heat to drive moisture out of them. The 8 minute cycle kills viruses and bacteria.

[batman]

Very cool project!

-Dennis

[uncle_bob]

Hi

A minor point: If playing with UV, you can generate ozone. Best to keep a window open while playing with this sort of thing.

Bob

[DavidsonOverlander]

Very cool project! The UV light that we use to treat our household water requires a particle filter to be used upstream because small particles in the water can block the light and reduce its effectiveness to kill bacteria.
With your system, how do you know that there wouldn't be virus in the filter material that wouldn't be exposed to the light? Or maybe the ozone would destroy them anyway. I should say that I don't have an N95 mask, so I might not know what I'm talking about!

[ProTech]

Set them in the sun for a few days, done.

[jeffmc306]

Turk123, you’re project sounds like something Doc Brown in Back to the Future would do! Have you considered Plutonium?

Jokes aside, Aptar, the company I just retired from has a really simple solution from our CSP division. They found a single strip of ActiveShield dropped in a gallon freezer bag with an N95 mask for two hours kills the virus. It releases 15 PPM of chlorine dioxide and the masks can be treated up to 10 times.

They’ve requested FDA approval for Emergency Use Authorization for the process.

https://www.csptechnologies.com/activshield/

[RWitherspoon]

We only listen to doctors and Medcram.com is a site where doctors can be trained, get credits for professional development.
We ordered UVC lights for our home and our children's homes after viewing their presentation which is in the last part of this video.

https://www.youtube.com/watch?v=2U4DAQ3kjRs

[HRTKD]

Wait a minute. If you don't look in the box, how do know the light is really on?

Kind of reminds me of Schrödinger's cat.


I've thought of using an ozone generator to de-stink my trailer. It can be a little hard on some materials. We've started to use it on our hunting clothing

[BagODoughnut]

I work in healthcare. 10 min of UV C on the front surface based on your geometry. Can do it about 10 times before the inner material breaks down. Or leave in an open brown bag for 5 days.

Stay healthy.