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I have 4 KingWin 850W power supplies running at 600W each on 240VAC. Apparently the power factor correction circuit makes a bunch of noise and the power supplies have poor filtering. I don't know if all power supplies with power factor correction are this bad since I don't have any other active PFC power supplies.

I'm selling pass through type noise filters for 7 BTC ~1 BTC. There is a standard 120VAC plug and 12 AWG cord going in to a plastic box and the same coming back out to a 3 way outlet. There's about 1.5 feet of cord total. Another option is to buy a 5 - 15 uF film capacitor with across the line (X/X2/Y2) ratings and wire it in parallel with your outlet if you wanted a cheaper solution that should still help quite a bit. It would be nice if you bought the filter from me but please do something! The noise from these things can be quite awful. We have a meter that measures electrical noise up to 100 kilocycles in a unit called "GS". At the outlet of the miners it measured 1800 GS (1999 is limit of the meter) and under 60 GS is considered safe. The 120v outlets in the rest of the house came up to around 400 GS because of this.

This IS NOT electromagnetic pollution. The air in the house between you and the wiring creates a natural capacitor of so many picofarads. This is direct electric exposure of small amounts of current flowing directly through your body. There is no magnetic component involved.

I have had small black spots appearing all over my body during the past year since I started mining and I have never had something like this happen before. Having all those spots that I never had before suddenly start appearing everywhere in such a short time period was quite scary. There is a very strong possibility that it is directly related. I'm glad I found out what was doing it!!!!  I think that 240V power wire that was running the miners runs right under the wall in front of my bed too.

Here's a copy of my ad in the order book:
One dirty electricity filter for BITCOIN MINERS using cheap unfiltered power supplies with noisy P.FactorC.. High frquency noise on your power lines is bad for your health! noise_voltage * frequency = how bad it is. 60cps * 240VAC is not as bad as 60,000cps at 1 volt. Don't learn the hard way like me. Contains 25uF of capacitance & 900uH of ind. total. Rated 30A 250VAC. Factory lead time 3 weeks.

edit: The noise at the miner outlets is now 800 GS and 400 GS on the filter input side. I was hoping for better. I guess the 2x450uH of inductance isn't enough even with 15uF of capacitance on the output and 10uF input. The rest of the house is down to about 110 GS.

edit2: I didn't want to center the conversation around the black spots thing. Lots of people have little black / grey spots on their skin. I didn't have such a thing until the last year which is why it was alarming to me. Putting the spots aside, here is a collection of research about dirty electricity and the various health problems it can cause: http://www.stetzerelectric.com/category/research/ . I was planning to put some kind of filter on the mining power supplies anyway before I had ever thought there might be a connection with the spots and dirty electricity.

There's a post below with a link to power supply inlet plugs with built in filters for only $5. You could add those to your power supplies and then add a 10uF X1/X2 rated film capacitor to the inside of your power strip along with a bleeder resistor. For four power supplies that would only cost you about $32 + shipping from Mouser.com. 2x450uH of inductance is still too small but it would help.

Maybe start taking a shower and those black spots will stop accumulating.

http://www.quackwatch.com/01QuackeryRelatedTopics/emf.html

what the fuck did i just read.

op, either you're an idiot or just has skin disease.

1++ year of mining, and my skin is still as good as before.

PSUs aren't causing any sort of health problem. Cellphones don't hurt you either.

http://upload.wikimedia.org/wikipedia/commons/thumb/c/cf/EM_Spectrum_Properties_edit.svg/675px-EM_Spectrum_Properties_edit.svg.png

Most of everything smaller then a wavelength of Ultraviolet has the potential to cause burns. Gamma rays are particularly cancerous due to their size. It goes right into you Cell -> Nucleus -> Chromosomes then slices up your DNA (and RNA). Your PSU will not emit wavelengths anywhere near that. Much closer to Radio (particularly AM).

Millions of people would have turned completely black by now if this was true.

Can I rend the apartment next door and set up a microwave oven with the door open facing your side?

Tis not a problem. 
I wind the extension cords from my miners and place it over my head to keep me warm.  I thrink it hellps my think butter!

Mmmm....sourdough toast and melted think butter.

Mad scientist indeed...

Are you sure your black spots aren't a result of chemtrails?

This is bullshit.
If not bullshit, see a doctor, find out what's actually wrong with you.
Regardless, nobody wants to buy a "solution" to something that's not a problem.

Fucking con artist. 

I'm an electrical engineer, you're full of shit.

You may be having problems with your diet. Even check with a nutritionist first. Bitcoin can take up much of your time. Including vitamin deficiencies if you are having poor nutrition.

Isn't almost all of the wiring in a house insulated from the air by the plastic jacket surrounding the conductors?


Pics of spots plz.

Bubonic plague.

You all missed the obvious hole in the whole story: most miners will be hooked up to low-pass filters anyway. The surge suppressor in most power-bars will block radio frequencies. This can be a problem if you want to do things like powerline networking.

Tripp Lite ISOBar.  But you can buy inline power supply filters from Mouser for a few bucks. 

http://www.mouser.com/ProductDetail/Schaffner/FN9233B-10-06/?qs=sGAEpiMZZMsSuP4UBDzYOwl3D%252b%252bql6gQ4adt9tKgyqM%3d

Not sure if that would work as a retrofit in most powersupplies... probably not.

7BTC for an inline filter is some serious snakeoil.  Hit up mouser

this sounds like a joke.

Mad, yes.

Scientist, no.

Kinda breezed over the post but um, are we talking about .hack\\GU? lol.

Fuck you.

Seriously, fuck you in your face.  People like you make me sick. You remind me of the guy trying to sell blue green algae to stimulate stem cell production to cure diseases.

"I've been mining for 12 months, and I've had black spots appear in the last 12 months.  Therefore, BTC GAVE ME CANCER!"

Sorry for the aggression, but seriously.  Flimflammers like you piss me off. Whether you're doing it on purpose to make money, or because of your lack of education and ignorance.

You should introduce yourself to Brian Dunning at http://www.skeptoid.com  And teach yourself some critical thinking skills.

Scam.

Brian Dunning, FTW!

Hi, I run a mining rig myself in England. The hardware is as follows

8 x AMD 5870
8 x ASUS M4N68T-M LE v2
8 x Kingston 2GB DDR3 1066
8 x Corsair CX600 600W
8 x AMD Sempron 140

They are all out in the open with no cases or shielding of any type.

They are connected to belkin surgemaster power strips, and then straight into the wall socket.

Besides the bitcoin rig, we also have huge amounts of other computer equipment in the house, multiple laptops, computers, multiple quad screen setups, etc. Suffice to say we have a very heavy power draw in this house, and way more than OP.

I have been mining since May 2011.

I live in a 6 bedroom family / guest house. People are always coming and going, we have lodgers, lots of whom have stayed for more than 6 months, along with family who come to stay. We've had at least 10 people stay for >6 months in the same house as all this equipment.

None of my family, or any of the lodgers that have visited, have bumped into the issues you are speaking of, I have no black spots on my skin, and neither does anyone else.

Unless you can put forward some credible evidence that your black spots are caused by power issues (A letter from a doctor, perhaps?) I call this marketing FUD.

please, I hope no one believes this bullshit...

BFL has been announcing features out of thin air left and right, but if they could include one of the filters that Mad7Scientist is selling, I would quickly cancel all my other asic orders and load up on their Singles.

Which company can give me the fewest spots/Gigahash?

How is the OP's ignore button not highlighted yet?!  It should be dark orange with a big, flashing animated gif red warning lights or something by now, lol.

Hang on...

Did we just get trollied?

This isn't even electromagnetic radiation as your post refers to. These are frequencies in the 1 to 100 kilocycle range which is way below what are used for radio communications, except for some specialized things like the national time digital transmission (for those self setting clocks) and communications to submarines. Picking up these signals is done with magnetic detection since an antenna that is long enough is impractical because the length would be in the miles.

I am talking about voltage which comes in to your body through the capacitance in the air around you. It's like constantly touching two pieces of wire with a small but never ending high frequency voltage across them.

Cell phones and other microwave band digital transmissions are bad for you but that's a different story. Governments had to raise the safe exposure levels for certain microwave radiating devices to even be legal.

Look at the second picture on linked page below of the nose with the spot on it. Imagine something a bit smaller and possibly darker. Imagine them in fairly random places that are exposed to the sun, and also in places which are not exposed to the sun as much. At first a bunch appeared from sun exposure right after I first started mining, and then more kept appearing during the winter in random places. I never had such a thing happen like this and I've been out in the sun plenty of times. I continued to be in the sun this summer and it did not cause spots to appear more so in the sun exposed areas.
http://beauty-healthcare.blogspot.com/2012/02/how-to-remove-dark-spots-on-face-dark_26.html

That doesn't stop electrostatic force, which is how capacitors operate. The air and plastic between you and the wire creates a small capacitor. You would have to have metal shielding to actually ground out the electricity.

These are low frequencies which require much more inductance to block. The power supplies probably do have filters and those filters probably reduce the noise quite a bit but it is nowhere near enough. Those power strips are probably just a ferrite bead or choke with the wires wrapped around a couple times. It would help for something like 100MHz but it is nearly useless for this.

This noise sits right in the middle. With really low frequencies, it's so low that it's not harmful and the amount that comes through the capacitance in the air is very low. With high frequencies, small inductors and capacitors put in for EMI suppression easily block the noise. If you increase the frequency by 10, then 1/10th of the noise makes it through the EMI suppression inductors, and 10x as much is absorbed by the EMI suppression capacitors so you have 1/100th as much noise coming out.

You could spend your time pointing out real scams instead of helping suppress health information that would cause the mainstream medical system to lose money. Those people are the ones with the mult billion dollar scam going. The U.S. even went so far as to bribe officials in Ecuador to take a man who was selling herbs to cure cancer to the U.S. market on his website, and have him illegally extradited to the U.S. and put in jail.

Do you have a single transformer that hooks your house or a couple houses to the power lines or is there a split phase 240V line that goes down the street and hooks all the houses together on the secondary sides of the transformers? Having it shared might reduce the power line noise by sharing it with all your neighbors. This way is most common in residential areas.

Because most people probably find it mildly interesting and would not ignore it. Then there is a small group of people who are hellbent on being against what I am saying and you have to be able to see what I say to have a rebuttal.

Anyway, so far things are going all right. The GS meter measures peak noise so plugging in 1 PSU verses having 4 plugged in doesn't change the GS meter reading much. It is 750 GS with 3 on and 800 GS with 4. There's still 400 GS on the filter input side and about 120 GS in the house. With some added capacitor filters it's down to 70 GS on those circuits. Everything seems to be working fine. I haven't gotten any new spots, but it's only been two weeks. Besides, I was going to add the filter anyway before I ever knew anything about spots. So either way I'm happy.

The spots are kind of weird. It's like there's this black stuff under my outer skin layer skin like a tattoo. I scratched off the outer layer of skin over a spot and I scratched this gummy dark stuff out. There was just a tiny bit of blood in that layer. Then it healed back to being normal with no spot. You guys are probably going to be all upset that I scratched my own skin without having a doctor involved and dared talk about it. Talk about a scam.

You really have no idea what EMR is, do you? Read up on Einstein's Wave Particle Duality before spewing more shit out of your mouth.

You guys this isn't a freaking joke. This is serious. If he were to not use these filters, it's inevitable that he would turn completely black.

This isn't the first time this has happened either!

If you'll recall, there was a black guy that had this happen to him, started getting white spots.

Short time later, he's completely white.

Yes, Michael Jackson was the first for this to happen to, he was living in a house full of minors for years.

Boy,did get you catch me off guard or what  :D

Very well done sir !!!!!!!! 8)

I needed that laugh dude,perfect timing  ;D

Well cell phones are not good for people under the age of 12 iirc but only because the skull has not thickened enough to block the waves the phone generates. So kids should be fine texting, but not talking on cell phones directly on their ears. ( I worked for Verizon for 5 years so I got lots of research coming across my desk. ) Beyond that not much is going to generate anything strong enough to hurt you or anyone else unless your going to go hug your mining rig for hours on end.

Don't know what kind of research you were doing, but if you can come up with these kind of statements, I hope they didn't invest much in you.  Your skull thickness has no effect on blocking the cell phone radio waves.

http://www.greenhealthwatch.com/newsstories/newsmobilephones/childrens-heads-more-radiation.html (http://www.greenhealthwatch.com/newsstories/newsmobilephones/childrens-heads-more-radiation.html)
http://www.telegraph.co.uk/news/uknews/1565477/Mobile-phone-cancer-risk-higher-for-children.html (http://www.telegraph.co.uk/news/uknews/1565477/Mobile-phone-cancer-risk-higher-for-children.html)
http://www.cnn.com/2011/HEALTH/05/31/who.cell.phones/index.html (http://www.cnn.com/2011/HEALTH/05/31/who.cell.phones/index.html)
http://news.bbc.co.uk/2/hi/programmes/click_online/9554782.stm (http://news.bbc.co.uk/2/hi/programmes/click_online/9554782.stm)

Sorry it was the middle of the night, I meant radiation. But dang your kind of a dick arent you.

Funny how this forum is filled with technology nerds of all kinds and still most are completely ignorant to electromagnetic pollution. >_> Electromagnetic pollution is a real health issue, so no reason to ridicule the OP. In this case tho, I do agree that unless OP suffers from electromagnetic hypersensitivity there should be no health issue from switching PSU ripple. I would start to worry when a fluorescent light bulb can be lit via capacitive coupling, by simply holding it near the wires or PSU :D

Bad ripple at outlets can however cause problems to other electrical equipment, esp. old devices such as CRT TV's and monitors. It's very easy to get rid of ripple currents tho, and you don't need to buy expensive filters. It's easy to make such a filter yourself. Just take the power cord that goes into your power supplies and wind it into a form of a coil. Coils resist the change of a current, so with properly sized coil your 50Hz mains power can freely flow through, but the higher frequency ripple is filtered. Depending on the switching frequency of the power supplies you might have to make a rather large coil or use an iron core.

The suggested "capacitor in parallel" solution is a VERY BAD way to deal with the noise! Don't do it! Adding capacitance creates a short circuit for the high frequency ripple currents. The ripple no longer finds it's way to the wall plug, true, but instead, it's all dissipated in the capacitor and wires, which results in higher power draw, higher temperatures and generally wastes both electricity and your equipment.

I thought being a lying, scamming piece of shit was a reason.  Whether he's 5% right or not, this is the most blatant, idiotic bullshit post I've ever seen.

You know what, here's a frog levitating in a 10 tesla magnetic field, surrounded by enough EM radiation to do whatever it is you claim EM waves do to people, and yet there he is

http://www.youtube.com/watch?v=A1vyB-O5i6E

the frog wanted me to tell you that we're not made out of metal and you should all shut up.

argh. I should have read better. It looked like someone scared was looking for help and others just started mocking him. :/ Yea, there is a reason to ridicule the OP.

Funny fact of the day hm? Not so much. Static magnetic field is not EM radiation and does not "do whatever it is you claim EM waves to do to people". Earth has it's own magnetic field, what kind of an evolution would not get rid of life forms to which magnetic fields are hazardous? Say hi to the frog when you meet next time and tell him I want that machine to the nearest amusement park.

I assumed people would put 2 and 2 together and I was lazy but the 2nd part of the post should have been...

So obviously all the electrical equipment around that device required to generate that kind of field is releasing enough "super dangerous OMG mega EM radiation" to give you a brain tumor and then cook it :P  There are probably huge transformers and capacitors, all killing everyone within a 1000 foot radius...except EM radiation generated by electrical equipment doesn't affect humans in any way :P or frogs, lol.

That may be the controversial state of the science, but depending of course on which kind of electrical equipment you mean.. it's not true. And it really sucks for the sensitive people.

My filter draws 768VA but it consumes less than 3W :)

Doesn't the Xc help counteract all the Xl anyway.

They have to come up with a reason for why advertising cell phones to children under 12 is illegal in France yet assure people that they are safe for everyone else. When phones were first coming out there was much more concern about this and the phone companies were saying all kinds of bogus stuff about how the radiation is so weak and a tree leaf would stop it.

IT GOES THROUGH THE WIRES FOR THOUSANDS OF FEET, including the 120v power lines connecting the houses on the block. It doesn't mater how close you are to the power supplies. It's all about the wires going to it, how far down the wire you are, and the impedance of the wire at each spot.

No need for accurate readings, really. IMO

Every PSU usually already contains an X2 capacitor, but it serves an entirely different purpose. When you switch off the power supply, the internal inductance (rather small though, in switching psu's) will create a high voltage peak that can be harmful to other devices in your house. The X2 cap is there to filter out just that and is not designed to get rid of continuous ripple. Though it works for that too, it's not at all a good solution.

You are not talking all bullshit with the "small capacitors in our body" thing. Capacitive coupling is a brilliant thing with a lot of potential: https://www.youtube.com/watch?v=jxqnyCnnTZM (skip to 2 minutes for the interesting stuff :) ) The device in video accumulates a high voltage of many kilovolts in the coil, able to light just about any kind of gas lamp. For what it's worth, I work with this kind of devices and have never had a problem with my skin, or any other symptom whatsoever. Your PSU does not create a fraction of this voltage, and even if it did it would all be sent down the mains wiring, not accumulated anywhere like it is in the video. So any energy coupled around is insignificant and the bullshit is right there with black spots and made up units (GS?).

Oh that is fucking priceless
 ;D ;D ;D ;D ;D

Insane conspiracy theorist / scam artist clue #1: everyone blathering on about "dirty electricity" and the harm that man made EMF can do are ALWAYS selling something.

And skateboarders too! lol.  Anyway, totally true :P anyone who thinks this is legit better look ANYWHERE else for their info on damaging EM fields and whatnot.

Btw don't forgot the golden rule!  If it has enough broadcast energy to cause harm to a mostly non-metal human body, the FCC already made it illegal for disrupting everything else :P

Feel free to ridicule the OP, but don't be such loudmouths about an illness you know nothing about. kthx.
You might want to get more familiar with RF signals, Desolator. "Humans are not made out of metal" is the poorest argument.

LOL,  Where do these idiots come from and how many idiots buy this kind of FAKE shit
COMMON SENSE PEOPLE

Where can I buy solar flare insurance for the absolute highest cost?

I sell the cheapest.  Only 99 BTC per year!*

* Insurance only pays out if purchaser lives past 126 years of age, has 3 legs, 2 biological mothers and is legally named Gerald Foffelby

Mad7Scientist i hope you dont believe this bullshit ur talking, otherwise your really lost!
Just a typical person crying for attention, well he got it a bit but in the wrong direction. i dont think he likes what were doing with him :P

Ah yes, EVERYTHING is harmful.  All the companies in the world are out to get you!  They know their products kill you and they're doing it on purpose as population control!  And you're so much smarter than everyone else for figuring that out so anyone who doesn't believe it is stupider than you, making you totally superior.

That's what these BS conspiracies are all about.  Every respectable study has proven cell phones do not cause brain cancer.  The ones that suggest it does are headline-baiting, scientific grant money-baiting assholes making shit up.  Remember Aspartame?  Remember the dozens of studies proving it does nothing?  It was a fake chain e-mail that suggested it does cause cancer and it convinced so many morons that I know people who still avoid Aspartame to this day.  But like I said, believing in a BS conspiracy like Aspartame is killing everyone when the majority of people don't makes you feel all warm and fuzzy that you're so much smarter than them.  Whatever.  Keep pretending everything that plugs in is killing you.

It may not cause cancer, but people are allergic to Aspartame :)

I just avoid it because it tastes like rancid buttholes.

I also agree that it tastes like ass, lol.  I do prefer Sucralose myself, plus that's heat stable at a higher temperature and tastes better and they use like 5x less of it.

I tell you to get more familiar with rf signals, you give me a newsflash about conspiracy theories? Well, thank you. There's no conspiracy.

I'd be more worried about chemtrails...

O.o

Okay, lesson 1:
It either can knock an electron out of orbit around an atom or it can't.  EM fields from everyday electronics cannot.  The end.

I was talking about your words "humans are not made out of metal" :D
RF signals (microwaves, to be exact) are reflected from metal objects. If humans were indeed made out of metal, we would have no worries inside a microwave oven. Instead, rf signals travel in a dielectric and humans being somewhat poor kind of a dielectric material, energy is lost by means of near field effects and microwave heating. Go educate yourself about those as well.

I made my point few posts back, let me repost it:
You say that this "EM radiation generated by electrical equipment" does not affect humans in any way. You are wrong, and you know it. There are many ways EM radiation affect people. Instead of showing total ignorance and disinterest, go see wikipedia for starters and if you're curious enough, tape a cellphone on your head, share internet from it to a laptop via wifi and put on torrent. IF ONLY you really weren't too busy being intelligent and teaching me your lessons about conspiracy theories and ionizing radiation, you could really learn something about electromagnetic hypersensitivity and why it such a big deal to some. It should interest you, if you're going to keep on being so loud about this subject. The talk will not end to hundred scientific studies proving EM radiation harmless as long as it causes symptoms. Whether it's just meaningless allergy needing treatment (which I hope it is) or a serious problem is sure interesting to me.

'tis true.

Microwaves vibrate atoms to cause heat.

Heat itself is EM radiation. That can damage.

Sunburn is EM radiation damage

X-rays... gamma rays... All a part of the EM spectrum.

How about 10 gigateslas?

http://en.wikipedia.org/wiki/Magnetar#Magnetic_field

In fact our bodies do contain metals.  They even depend on their presence.

You moron.

Radiation is radiation is radiation in NOT CORRECT

There are 2 different types of radiation. Ionizing (gamma particles) and non ionizing (tv, radio) radiation

Non-ionizing (or non-ionising) radiation refers to any type of electromagnetic radiation that does not carry enough energy per quantum to ionize atoms or molecules—that is, to completely remove an electron from an atom or molecule.[1] Instead of producing charged ions when passing through matter, the electromagnetic radiation has sufficient energy only for excitation, the movement of an electron to a higher energy state.http://upload.wikimedia.org/wikipedia/en/3/33/EM-spectrum.png

Ionizing (or ionising) radiation is radiation composed of particles that individually carry enough energy to liberate an electron from an atom or molecule, ionizing it.

With over 50 years of research there is NO EVIDENCE that ANY non ionizing radiation can cause cancer

Speaking of scams, what Zombie has advertised in his profile about pre-ordering the $1300 miner from BFL is more likely than anything to be a scam, but only time will tell.

Classic...

OP should be a pitch man for QVC

Who the fuck mentioned ionizing radiation or cancer?

Dickwad.

That was general information for the uneducated dumbarses.


NO U R!

0.o

Nah nah nah boo-boo, stick your head in doo-doo.  I bought a bunch of these http://www.trionz4sports.com/pc/ (http://www.trionz4sports.com/pc/) and wrapped them around my psu so I WIN! Your radiation can't touch me now, pfc's!

Any smart person knows to keep a plug in the socket... that way the electricity cannot leak out.

Why would he or anyone else need to get more familiar with RF signals when 99% of all PhDs and MDs are already in agreement on this issue?


And really I don't care how many resistors and capacitors you try to put on your power supply... how exactly do you purpose to stop the 60hz that's going to be pouring off every wire no matter what you do?  If it was really dangerous the only safe place is a cabin in the woods of Montana.

Well the good news is that all the problems that I spoke of originally have gone away or not gotten any worse. No new spots on myself or any family members.

I can't be 100% sure that the mains noise even caused it. A lot of people lately seem to have a mental disorder where they cannot comprehend something which is not absolute. If there's a 40% chance that the mains noise is related to health conditions, well they can't handle that. It has to be either it does or it does not. They rely on experts to tell them what to do. If the experts says that dirty electricity causes health problems, then they believe that it causes health problems 100%. Then they comply with the safe exposure guidelines. If the expert or government authority says that it does not, then they disregard it completely and make fun of anyone who believes it. It seems like a form of Asperger's syndrome or autism spectrum disorder. We all know that the level of autism spectrum disorders is exploding.

Some people believe the mainline story on everything. They believe what they are told to believe. They are told that small high frequency electric currents and EMFs cause no health problems, and that's what they will repeat to everyone. Now people almost believe that being overweight is not related to what or how much you eat. In fact, in the medical community it's generally frowned upon to associate various foods or food additives with diseases. High fructose corn syrup causes diabetes? Get out of here you crackpot! Are you a scientist? No. Mad? yes.

I hope somebody may have benefited from this. If you found out about a health hazard would you try to tell others? Sadly, probably not.

We're all talking about PSU ripple currents here, typically around 10-30KHz. Not the 60Hz mains frequency.  ;)

No new spots after all this time!!! I've had the 10uF and 15uF of capacitors with the incorrect common mode inductor and then several 120v outlet ones plugged in as always. The capacitors must be doing the job!

Great news!!! No spots whatsoever for me either!!!

Added benefit for me is that I didn't blow 7BTC on pass through type noise filters.  ;)

Me too!  I have a 49,000 watt farm with 61 PSUs and I haven't been affected!  His filters must work from a distance!  No need to buy!