You are welcome :) The mechanisms are the micro level are quite complex, but a basic understanding is always so important so that the technology is appreciated….
From microbewiki- as an independent reference and for general clarification to those interested. Cell Structure An identifiable trait of coronaviruses is the club-shaped spikes, resembling solar coronas, that project from the cell membrane. [2]. The nucleocapsid of coronaviruses has a helical shape, which is uncommon for positive-sense RNA viruses [2]. The virion shape is spherical, with an average size of 125 nm [2]. There are four main structural proteins: spike, membrane, envelope, and nucleocapsid proteins [2]. The membrane protein is the most common, and is thought to be responsible for the spherical shape of the virion [2]. Viruses that do not have the envelope protein expression are not lethal, though further research is needed to confirm this hypothesis [2]. The envelope protein can vary among different species of coronavirus, but its responsibilities include gathering and releasing the virus to allow it to infect a host cell.
This is true to a point, he's basically talking about a "droplet mask" where the sieve mechanism only applies. HEPA uses three different principles for function.....interception, impaction and diffusion. In the world of viruses, specifically COVID-19, diffusion is your main friend. Where the air flow through the filter causes the particle (virus) to change into a turbulent movement pattern and adhering to the fibers. So yes, it can filter down to 125 nanometers.
The government and the CDC have a tough challenge - people are a complex mixture of rational and non-rational reactions, as we all know. Authorities have to balance these - if they are completely rational and ignore “the reactions and fear” of people, they would be accused of fear mongering. In some of my videos (I am a rational PhD scientist) people proclaim I was fear mongering. So the facts sometimes create irrational fear. A nice example is a shark attack on a beach. If an attack happens once every 10 years, people will actually “have a fear to swim”. But, the number of car accidents involving injury is FAR higher than those who are attacked by sharks - but the same feelings of “fear” are not felt. So the CDC and the government have to balance information with “fear mongering”... fear is not a good thing, because it results in irrational behavior, and irrational behavior can lead to unintended terrible consequences. For me personally, I learn, I research, I teach, and I think. I am also in business to feed my family, and hopefully I will create, conceive more inventions, and ultimately bring them to reality. Here on RUclips, with my limited social media skills, If I can bring understanding, I will do it. I appreciate your positive comment Will Brito....
@@bluesky-globaldr.michaelse6427 excellent reason. especially "Fear only hinders." I wanted to learn and research which made me land on your account. Thanks again!
Don’t listen to the CDC they are telling people it’s OK to wear cotton masks which wearing them is better than nothing. But nevertheless you will get sick and catch the virus with a cotton mask this is why I don’t like what CDC is saying
Will I don’t think that is entirely true, honestly putting your arm in front of your face is better then nothing. I don’t think you can catch a virus by wearing a mask
according to a controlled study, a hepa filter (13? - "conventional" hepa the author wrote = 13?) will filter sars-cov-2 droplets/aerosols by " 85.38%" in 1 pass/cycle of room air, 96.03% after 2nd pass and >99.97% after the 7th pass - how fast for 1 pass depends the air purifier's power
OK, understandable. So now you got a hepa-filter filled up with saliva and mucus droplets and lots of viruses within those droplets. As soon as these droplets get caught they undergo rapid evaporation due to the forced air molecules through the filter bumping into the droplets, they evaporate allowing the virus's to break free from the droplets little-by-little and tumble through the hepa-filter netting reintroducing them into the air not attached to any droplets. Does this sound like an accurate analysis?
rcs300 - yes. That is why I have incorporated UVC filter surface sterilization in my BlueSky Defender machines... to exactly prevent it from happening. Thank you for your comment and observation
The material in the vacuum cleaner bags is called HEPA which is a kind of glass microfibers mat. It is widely used nowadays, you can find it inclusive in your car. The problem with wearing it in a mask can be potentially dangerous since there’s evidence that exposure to glass microfibers increases the risk of respiratory and skin symptoms (as said in the article above).
Dr. Seitz does it mean that nowadays pertains to new normal restaurants or other related events, despite of limiting a number of attendees, one must have HEPA Filters as an added service in the deployment of safety protocols most especially in this type of industry? because the old normal do have air conditioned units to attend customer needs without even thinking the importance of filters but rather focus on a cooling experience to complete the ambiance.
Hi :) this is a good question, and can be answered from various perspectives. From a strictly COVID-19, duct downflow air ventilation with HEPA filtration and UV-C integrated sterilization provides the BEST risk reduction of all methods out there, other than staying at home and never seeing anyone!. Why? Because social distancing only works if people never move. Imagine standing 6 feet from someone with COVID (maybe they don’t know they even are sick yet), they move forward to pay at a checkout, and you walk INTO their space - how did social distancing really help you avoid breathing in contaminated aerosols. SO, continuation ventilation brings clean air in, remove the bad air all the time. Obvious stuff. But the cost of installation falls on the business owner, landlord, etc, and that is a hard pill to swallow. Must easier to say wear a mask or wash your hands. The next perspective is that of just general smart air - where downflow improves the quantity of air dramatically all year, allergies “vanish” indoors, cold season and Flu season are much less dramatic etc. So a new normal could just be healthy air (the way we now drink bottled water mostly). Blah blah long explanation - point is - clean indoor air should be a new normal, for all sorts of reasons, but will public opinion and buying power force businesses to change and make us all feel really well because the air smells GREAT and clean....
SAMSON SL - yes, bringing in new HEPA filtration and downflow designs with protect people and improve the quality of life for indoor spaces. I am trying to spread the word, including with my own invention in BlueSky, to bring healthy air. Imagine all the people with allergies, or cold or flu season - misery indoors will be significantly reduced.... all it requires is a determination to change and improve designs
Don’t use in masks! They are meant only for use in air filters/purifiers. Do NOT inhale through air filters. They contain fiberglass & aren’t effective! Please watch. ruclips.net/video/qiYbXsIcI7E/видео.html
sheeplvl1 HEPA filters specifically are not worn. But generally speaking with filters, and face masks - “dried” residue usually remains trapped on a surface. Let me use a silly but informative example. If dust laden rain drops settle on your car, and dry, the mess on your car would be apparent, and you certainly would not be able to “blow” off the mess. Stuff caught in filters usually stays there by “surface bonding effects” best left for a science class. The practical example on a car being dirty and driving fast NOT cleaning it, is a simple example of “small stuff sticks”
Treebeardshome . So HEPA filters should be banned from use in air recirculating systems? We have those in homes and offices working 24/7 and are breathing in the junk filters put out themselves? I don’t think so.
Covid-19 is a big bigger than 20-30nm. It is 60-140 nm. The droplets were said to be about 500nm. But the filter is also more like a maze than a lattice, so it can still capture individual particles much smaller than 300 nm. [nanometers]
Correct Gary. In my discussion I was referring in that instant to the smallest of the viruses - COVID-19, relatively is a “large” particle virus. And yes, under a microscope, the structure of a filter fabric is a 3D “mat” of fibers, with largely random orientation. For the sake of visualization of the idea of catching something, it is useful to simply concepts. There are a lot more issues to add - for example, once “dirt” gets onto the fabric, the filter improves in filtration efficiency as so on... but in essence, the description as I presented illustrates why a filter with a 0.3um 99.97% specification can be so useful for small viruses since the viruses are actually contained in aerosols. Thanks for your comments Gary
@@bluesky-globaldr.michaelse6427 I also noticed in JAMA, that in real world large study, they didn't find any significant difference in infection of health care worker in Surgical vs N95 masks, although they didn't think it was a failure of the masks. jamanetwork.com/journals/jama/fullarticle/2749214
Garry, it is so dependent on what “study” you read or cite. In a nutshell - it is proven that we expel the virus in mucus/saliva when it sheds. So release and “outward” is clear. It is also well established the leaves an infected person by droplets, with the vast majority in the form of aerosols (
let say the virus is not submerged in mucus or other type of matrix except the air. How significant is the brownian motion effect towards the virus which causes the virus to kind of 'bouncing' around in the air and made its effective radius bigger
Of course there are possible hazards or side hazards when converting a vacuum bag or any other type of HEPA filters into an usable mask for protection. I have built several, but I don't use the HEPA material solely itself. I sandwich it between layers using the pattern: cotton, charcoal, HEPA, charcoal and cotton. Oh btw, the type I build are more of the military style (M17A1) with the screw-in side filter with inflow and outflow valves.
Please, true HEPA filters have a high resistance to air flow - essentially, they are hard to breath through. SO what happens is that when you put on a home made HEPA filter, the air struggles to pass through the dense fabric of the HEPA filter, and BYPASSES air between the mask and your face - simple leakage - because the air wants to find an easy pass. SO unless the mask is physically sealed against your faces, the leakage at the edges will increase (using a dense HEPA) and do LESS good. In a car, or in a machine such as the one BlueSky makes, leakage is prevented by dense rubber seals, and air is forces through the filter. Please, don’t make a HEPA mask, you are going to force more leakage and make the mask less effective. The best combination is good air circulation and air filtration in the public space, and a mask to catch the heavies (cough and sneeze droplets). Hope this information helps... watch my new video to see what system I am suggestion for air cleaning.... follow my channel and share please.
@@bluesky-globaldr.michaelse6427 Uh...Sorry and Hate to inform you, since clearly you have a much better understanding of HEPA filters than my 27 years of military experience and after reverse engineering an actual M17A1 Nuclear, Biological, Chemical (NBC) filter. Also in your hast to criticize, you should've first either study the working of a M17A1 NBC Mask or further invested you time in reading and understanding "Inflow and Outflow valves" But once again typical, quick to criticize without any understanding of the subject at hand...Sounds so familiar of some else.
Michael Angel, if you read my comments, it would become apparent to you that I never reference M17A1 NBC masks - I am pleading with folks wanting to make masks for themselves from vacuum cleaner HEPA filters..... I actually reference engineered masks as OK. Masks without proper face fitting seals that have high efficiency do not work because of leakage.... as you can no doubt confirm, a high quality mask requires a high quality seal, shaved face for men, etc.
Michael Angel , please consider that most folks are not familiar with inflow and outflow valves, Carbon adsorption, etc etc. It is not useful to explain high tech advanced mask making when most folks are fearing infection but don’t have advanced knowledge or any desire to research nuclear, biological and other advanced equipment. So as a closing comment, teaching is valuable, but also remember that 27 years of military experience is an experience you have, but you are one in a few experienced and highly knowledgeable people out there.....
@@bluesky-globaldr.michaelse6427 I post my information on how to properly construct a well fitting mask from using common items which most people throw away everyday. In my videos, I go through several topics (Why a cloth mask is your worst option, but is better than no option at all, Why is cotton used, how and why charcoal is used, Why is a HEPA material used, and how they traps smells, viruses, etc, without using an outflow valved system is both a waste of your time and dangerous, etc.) I also demonstrate how you can use everyday items with slight modification to serve as your both In & Outflow valves, how you can use window adhesive seal (from Walmart) in making an air-tight fitting from the bridge of your nose to below your chin area, I demonstrate how to convert smaller containers into the filters as described in earlier messages and I do all of this for free. Closing: Yes, after building my masks which uses a HEPA material sandwich between charcoal and cotton and from the principles of military's M17A1 protective mask (using your natural inhalation and aspiration of breathing to open and close valves) your breathing isn't as "Free Flowing" as breathing normally, but considering your options of being dead and not breathing at all, most will gladly op for the fore-mentioned. Again, I don't do it for "Likes" or "Money" or "Subscribes" or "Followers" I do if for free, because I'm an American whom served his country proudly, care about those whom I served; this is a time when it's not about the one, but about the all in providing correct information and helping regardless of their color, political opinions, religion, sex or whatever....it's not "Make America Great Again" but "Make America Strong Again", "Make America Heal Again" and "Make America One Again"
sheeplvl1 virus are too small to be caught simply by a hepa filter, but most viruses are transported through water droplets in the air by a sneeze so wearing a hepa mask definitely does help
Yes…. Absolutely! The key to effective filtration in public spaces is 3 folder: 1. High air exchange rate (12-18 times per hour at least, 2. Air flow direction should be predominantly vertical down flow, so blowing into the space from above, and sucking out at floor level 3. HEPA air filtration to capture aerosols. This is EXACTLY how air exchange works on commercial aircraft. Building owners/companies are hesitant to implement such systems (my company has full retrofit instal designs) because they don’t want the hassle or the cost of an install. But it is so doable and is the only thing that really makes public spaces safe. More than 2 BILLION people have taken flight since the beginning of the pandemic…. And super spreader events on planes are virtually unheard of. Public spaces should invest for everyone’s future
Great illustration! However you will not be able to prove it since in HEPA integrity testing we are only looking for 0.3 micron. The criteria would be anything below 0.01% of the up stream challenge of the filter. If you are injection 25,000,000 then the allowable particulate amount would be close 2500 ppm at 0.3 micron. The retention rate would be 99.9900. So anything smaller than 0.3 micron has the opportunity to pass through. Filters are rated for 0.3 micron throughout the industry and the iso criteria for testing is the same. We do not have data to back up anything smaller
Hi and thanks for your explanation. What would be the effect of treating the HEPA filter with a quaternary ammonium compound that binds to the surface of the filter? Have you got methods of testing it's effectiveness?
Unfortunately, this is incorrect explained, yet outcome is the same: HEPA grader materiale after the EN1822 standard (classes h10-h14) Will stop almost everything from 300nm to 0nm due to random brownian motions effect on particulates. So even if isolated virus would float, it would be captured. Please also note, slow airflow across the filter media will increase particle collection effecency and also lower power consumption og fan - yet clean less CFM in a given time interval
Acetylsalesylsyre, you are correct of course, but the specific detail mechanisms are not always required to understand the principles of “capture” - that capturing “encapsulated” or agglomerate particles is different from capturing the constituent particles. I remember a similar analogous discussion - looking at the constituents of table salt - table salt goes well on fries, but the constituents are Sodium and Chlorine - neither of which go well on fries. So the viruses may be small but they are a component of an aerosol - HEPA filtering is looking at the catching the aerosol “VEHICLE”, not the particles within the vehicle.
I thank you for this video, though I have a question. How are the "corona viruses" trapped inside the droplet, since covid19 is an aerosol? Does it create something like a thin air layer or?
The viruses that are shed from the infected person transported within the infected person’s saliva and mucus. Essentially, your entire breathing tract is “wet”. When you breath, or cough, small aerosol droplets are continuously being breathed out. Think of yourself as a “fogging machine” - if your breath against a cold glass (or if you wear glassed with a mask), you will see how “wet” every breath is. In these invisible droplets, it is possible to harbor the dangerous viruses, and for another person to breath them in since they float and are invisible.
HEPA works, correct. But what happens when the droplet will eventually evaporate? Will HEPA release the lone virus particles into the air? I think this is the place where UV light comes in.
When that particle evaporates, the virus particles can then pass into your lungs, the droplet that allowed the virus particles to be captured is now gone. Is this why we change out our masks?
So if the water droplets eventually evaporate what do you think happens with the viruses that were in them? After a little research I'm convinced that the virus is much heavier than air as is liquid water. The ability of tiny water droplets to hang in the air indefinitely until they evaporate indicates that they must be expanded with a depressurized core like a vacuum balloon. A preference of water molecules to be in the surface may cause this. If it grows more massive it would collapse into a full liquid state and fall out of the air as rain. If the droplet is buoyant in the air it wouldn't be able to contain many heavy viruses before it would begin to fall like a hot air balloon with too many people in the basket. Bottom line is that gravity plays a major role in keeping transmission rates down by pulling viruses out of the air. But with a virus like covid 19 with a high rate of replication, gravity's work may need some help. Things like inhale filters placed up high with air entering from below and exhale air exiting from a low place would help. Keep in mind that when the water droplets hit the filter they may still evaporate leaving dry viruses which may be stuck between fibers or may pass on through. It's good to keep the flow rate low by using large filter surface area with air flowing up so gravity helps stop the virus passing through.
Wesley, fine particles, aerosols, behave a little differently from rain - as surprising as it may sound before you actually test it, and explain it scientifically (which can be done easily), let me say that under 5um particles floating “indefinitely” - they do not sink down despite being “heavier than air”. Google this to get all the explanations - but here is the important thing.... aerosols WILL float, drifting with the airflow. So if you breath out infected aerosols, and there is NO ventilation and filtering, they will remain airborne and other WILL breathe them in. In the same way a smoker leaves behind the “smoke” in a room with closed windows and no ventilation, the same way we leave behind aerosols. That is why HEPA filtration with good airflow design is so important in combating the spread of Coronavirus.
@@bluesky-globaldr.michaelse6427while quite certain the phenomenon is real, I dismissed the explanations I found for aerosol droplets not falling. One was that the size was too small to be affected by gravity but if the much smaller photon were not affected by gravity then black holes wouldn't be black. The other was insufficient because despite the high ratio of surface area to weight since the droplets are so small it still requires small updrafts to support the droplets weight. This might work for clouds but not fog since the wind would have to be coming out of the ground. It is also unlikely the rising air would be so regulated as to make the droplets not appear to rise or fall. After observing a good deal of time lapse fog videos I concluded that the droplets must be the same density as air. Since the liquid water is heavier than air the only explanation I could imagine is that the droplets are acting as vacuum bubbles. This probably doesn't make a huge difference because even a little air movement will have more effects on the droplets than gravity but I like to be able to visualize what's actually happening. I do think however that the gravitational effect is greater if the droplet is carrying many viruses. This would make them increasingly different from fog or cloud droplets the more viruses they contain. Of course one virus is enough to have a possibility to infect a person.
Wesley, let me try and shed some light on this phenomenon using a simplified explanation - when a particle gets really small, the gravitational force pulling the particle to the ground exists, but is real actively small. At a small enough size this force is low enough that the air “making way” because higher than the downward pull. So think about it this way, the particle is like someone trying to push there way through a crowd.... the crowd being air molecules.... when the particles get small, it simply stays where it is “floating”- like a person unable to push his way though a crowd because they dont have the strength. Now a fun experiment.... take a flashlight with a strongly focused beam, and shine it in a dark room. In the beam you can see floating particles, that don’t fall to the ground but float in the air. Those particles are denser than air, and solid - but there they are floating are moving around like the dance of the fairies. Rays of sunlight through a window will also show all the floating stuff in the air. One final analogy, you can place a very solid heavy brick on loose sand, and despite the brick being much denser (mass per unit volume) than the sand, the brick will rest on the sand and not force its way through the sand. This illustrates that is takes more than gravity and a dense mass to penetrate non-solid substances.... sand is easy to penetrate, but given the right conditions, it can support huge loads.... just the way air can keep aerosols suspended despite them being significantly denser than air.... hope this helps a little
@@bluesky-globaldr.michaelse6427 I appreciate your time to discuss this and hope not to distract you from your mission to help people breathe clean safe air. I just see apples to oranges comparisons when air is 99.9 percent empty space. With these molecules jostling about to maintain their level of heat it seems there can be no static friction so any small constant force should eventually overcome the air resistance. I believe the dry particles in the room are suspended in the air by static charge but I think water is too conductive to hold that level of static in a small space so it seems the vacuum bubble idea is a good explanation for aerosol droplets not falling. Another fact that supports the idea is that light would diffuse through empty bubbles as we see in fog and clouds but would refract through the droplets when filled with liquid water as we see when the sunlight makes rainbows in the rain.
The HEPA filters should also have UV-C light. Open areas should have 222 nm ultraviolet light. The most vulnerable should have it in their HVAC systems. Most homes have ultraviolet light in their HVAC already. Nursing homes need at the most. The far UV- C should be in supermarkets, factories, schools, etc.
This explanation also assumes that the droplets that envelope the virus particles stay intact when passing through the filter. If the filter actually causes the droplets to break apart, it could be making the problem worse rather than better.
Could you please explain then why breath with water content still makes its way through several layers of mask or hepa? Does hepa stop 1 micron particles?
Potentially, but the formites on the filter surfaces most likely will remain “attached”. The BlueSky Defender machine which I invented which uses HEPA filtration, has a built in UVC radiation source within 2 inches of the filter surfaces to destroy ANY captured viruses. The most important design consideration I used is the UVC light need exposure time to act, and the potential viruses within the HEPA filter “fabric” will be neutralized effectively. Killing viruses in free flow air within air ducts is totally useless in my opinion, but radiating surfaces for longer periods is an excellent method of destroying pathogens
Nikky, 100% is actually never required.... we strive for 100% of course. For coronavirus, this key is to reduce the loading (concentration) of viruses in the air. For machines like BlueSky Defender (my invention) the concept is to significantly reduce the aerosol (and all the bad stuff in general like allergens) to levels that are very low. The biggest danger we face at present in most indoor spaces is that clean air ventilation is very low in the winter and summer months if air conditioning is present. In public spaces, I always recommend at least 12 room changes an hour, with HEPA filtration of the circulated air. Spaces with such ventilation are MUCH safer....
01 s o n g s - refresh rate is very very important, because it reduces concentration. So think about it this way... if people are smoking in a closed room, the concentration of smoke would build up quickly and become choking quite quickly. But if you opened a window, some of that smoke would drift out, and improve matters. Open two window on the opposite sides of each other, and create a strong cross draft (maybe windy outside), and you would remove the smoke much more quickly and the concentration would no build up. Smoke are “aerosols” - we see and smell that - with breathed out aerosols they are “invisible”, but still behave exactly like cigarette or cigar smoke....
Good explanation ! However, that means one can therefore indeed use almost any material, such as coffee filter paper etc, as a mask, since these will surely catch mucus droplets..
Maaifoedie De La Rey - HEPA filters are used in “machines” as a very effective filters of the highest quality we can currently manufacture in volume. I think one of the misconceptions is that HEPA is intended for breathing masks - HEPA is intended for filtration systems for spaces where pollutants and pathogens are present - for example a plane, a hospital, and even modern cars. For the currently challenges we face, I am strongly suggesting in my work that HEPA filtration systems be installed in large public spaces, so that the air WE ALL HAVE TO BREATH when we are in these public spaces are a “clean” as possible. In the same way, we want the water coming out of our facets, the food we buy at a store, to be clean. It has always amazed me how conscientious we are above safety, but he air we breath is often “not great:. HEPA filtration in public places goes a long way to improve the situation, and reducing health risks...
There are various size estimates, all in that “range”. However, the individual size is not as relevant as the viruses are shed and expelled in mucus and saliva, and these particles are much bigger. In essence, filtration captures the “transport vessels” containing the individual virus particles
You are welcome. I made another video to dive into some of the aspects affecting virus transmission... ruclips.net/video/MQ-gyjoDFts/видео.html If you like it, I will continue to make more of this kind of video :)
I believe that the person in this video who is explaining about the HEPA filter at what microns does it filter out viruses I believe he is wrong on the microns that HEPA filter does filter out. If it is authentic five layer HEPA filter then it will filter out the same as N 95 mask which is 0.3 µm so I don’t know why this gentleman is saying that HEPA filter only filters 1 µm which is not true because it filters 0.3 µm
Don’t use in masks! Only in air filters/purifiers. Do NOT inhale through air filters. They contain fiberglass & aren’t effective! Please watch. ruclips.net/video/qiYbXsIcI7E/видео.html
Angie Corona Please DONOT make HEPA filter masks.... HEPA filters are used in machines like we make at BlueSky for large public spaces. They are not useful for people, and no HEPA filters masks can be bought - they can’t be breathed through. If someone offers you such a mask, it is fake... or if it is a real HEPA laminate Fabric, you will not be able to breathe through it normally.
This is an interesting question, and is highly subject. Objectively, I would say that “ductless” systems have limited value in public places. However, if one is used, the best location would be on the side of the desk others sit - you don’t really want to draw air others have breathed out over yourself toward a machine placed behind you. But again, in my opinion and based on flow dynamics (I am an engineer) the only truly effective solution to safe air is downflow ventilation with HEPA filtration of the return air. I have dedicated my life at this time to try and educate on this topic, and also provide equipment that can serve in the role (my company BlueSky-global has developed such large machines for placement in large offices, call centers, waiting rooms, and retail lineup areas where cross infection risk is highest).
People are wearing masks that are three layers of cotton. Thinking that those are filtering out particles When you inhale? And Exhale? So .... What's your feeling about ever flow personal filtration devices that filter air before it enters your mask. They're using a HEPA filter with charcoal in it to filter the air before it enters your mask. What's something like this filtrate the Coronavirus applied to an n95 mask or cotton mask three layers thick?would think I could just use three layers of cotton in there. Or I could cut up n95 mask and make a bunch of filters out of it for a device that filters air
Flaming Polish Hillbilly - masks are an essential primary protection we take personal responsibility for. I suggest a basic mask is better than no mask. In essence through, I feel that without proper indoor ventilation (as I have spoken about at length on my other videos) there will be continued major cross infection.
That is a good question - and not easily answered. The “dry” mess is still a collection of particles (stuff). I think it is sufficient to say that we should be most concerned with “fresh concentrations” of aerosols in stagnant air. There are many mechanisms where, say, captured aerosols in HEPA filters kinda “stick and stay”, rather than “wiggling their way” out. In general, at the micro level, filters work in a multitude of way to catch and hold very small particles. To me the most pressing question is “why is there not more emphasis on air ventilation in public spaces”. Any ideas, anyone?
Ohhhhhhhhh that actually makes a lot more sense, so in theory if someone wore a true hepa filter face mask and they had a virus would other people be ok?
@@saltymat2052 u clearly had no clue. medicine.uiowa.edu/iowaprotocols/n95-respirators-hepa-or-high-efficiency-particulate-air-filter-respirators-personal-protective
@home media 😬 for you because you are going to spend all that time adding a HEPA filter to your mask with out realizing that the air will just travel through the sides instead. Once again plz don’t thank you:)
@@saltymat2052 do you have research evidence? Doctors have used hepa respiratory mask(pre cov!19). It's in article I linked. Do you have any proof I can work with? What is this "research" you speak of? Comparable to uiowa medicine?
Absolutely…. If the air flow is sufficient (say 18 room changes per hour), and the flow direction is from above to floor predominantly, together with HEPA filtration, the risk of cross infection is HUGELY reduced
@@bluesky-globaldr.michaelse6427 Oh, thank you. Yes, 18 complete air-cleanings of the entire room within one hour (= one complete room cleaning in 3,3 minutes:). On highest mode...and it´s Hepa 14. The Filter sucks the air in at its bottom and releases it vertically towards the ceiling. And my daughter (7) would sit on one side of the filter, and me on the other - at least most of the time. So I can´t infect her(that´s my big worry). Because I saw how the virus can make even children very ill. What´d be your opinion? Thank you for answereing. Good health to you and your family:-)
@@benstiller500 The flow is not quite as you describe. The air is “pushed” from above, and sucked in from the floor area. So top to bottom. Like on a commercial plane. If you go to this web link there is a picture to show you… let me find it and paste it in a reply to you
Hi everyone, I made another “explaining stuff” video relating to the virus and seasonality ... check it out and let me know if you would like to see me make more ruclips.net/video/MQ-gyjoDFts/видео.html
Hi Sarah... using technology that can filter such small particles is of very little value. The particles that we need to “not breathe in” are typically larger than 0.3 microns and up. The reason I say that is that individual virus particles (as those we see in virus depictions and diagrams) are really not real - the method of transfer from an infected person is in mucus and saliva, so as I tried to explain, like a raisin bun. Let me ask you, why did you endorse the 0.007 micron idea?
HEPA masks.... I made a short video specifically on this topic.... please share, and follow me if you are interested in Aerosol spread science and novel thinking regarding “what may be happening” ruclips.net/video/DIYIAErKtAo/видео.html
Hi all, I have published a new video on how I believe we can prepare for a potential second wave of the Coronavirus. Please watch and share ruclips.net/video/x7wqZK2wIpA/видео.html
Scott, not sure how you draw your conclusion, but having an understanding of how things may work, it always useful. Disagreeing with an explanation is certainly part of a good discussion, but linking ideas automatically to “huge danger” may be a little too dramatic. Would be interested though in your thoughts on virus transmission mechanisms, and how to limit spread...
@@bluesky-globaldr.michaelse6427 I worked in Hazmat and was Lic . Only Full SCUBA can protect You from Viruses ! And only if the air tank air is clean of viruses !
John, it is time to be pragmatic - reducing concentrations of viruses is the critical factor. It has been extensively shown that with low concentrations of aerosols, the risks of contracting Coronavirus is hugely diminished. Think of this analogy - as crude as it may be - if a couple is trying to fall pregnant, and the man has low sperm cell count, it is very tough (but possible) to fall pregnant. In the same way, a room that has 12 room changes of air per hour of HEPA filtered air is MUCH safer than a room with minimal ventilation and no HEPA filtration. We need need to shoot for perfect, we need to shoot for low concentrations that are MUCH safer....
@@bluesky-globaldr.michaelse6427 This Corona Madness is just that madness ! Only SCUBA will work, and only if the air tank is virus free ! Get rid of the masks and let Your immune system work !
John - some people do not have that option because they have compromised immune systems and other complications. We are trying to protect the elderly - those folks we can thank for being moms and dads, and citizens who also deserve care. If we have outbreaks (waves) that exceed hospital capacities, such as those in Italy for example, we are face with triage, and frankly, that is terrible. Imagine your own parents potentially struggling to breath and facing a terrible end-of-life experience. Perhaps it is better to take better care of the air quality?
Very good. To many ppl talk about virus size but virus or bacteria need a transport media.
Superb sir
As an industrial hygienist Finally my all doubts cleared through your easy explanation
Thank you for this, very simple yet straight to the point discussion about HEPA filter.
You are welcome :) The mechanisms are the micro level are quite complex, but a basic understanding is always so important so that the technology is appreciated….
From microbewiki- as an independent reference and for general clarification to those interested.
Cell Structure
An identifiable trait of coronaviruses is the club-shaped spikes, resembling solar coronas, that project from the cell membrane. [2]. The nucleocapsid of coronaviruses has a helical shape, which is uncommon for positive-sense RNA viruses [2]. The virion shape is spherical, with an average size of 125 nm [2]. There are four main structural proteins: spike, membrane, envelope, and nucleocapsid proteins [2]. The membrane protein is the most common, and is thought to be responsible for the spherical shape of the virion [2]. Viruses that do not have the envelope protein expression are not lethal, though further research is needed to confirm this hypothesis [2]. The envelope protein can vary among different species of coronavirus, but its responsibilities include gathering and releasing the virus to allow it to infect a host cell.
Finally I understood it . THANKS FOR THE BRIEF & CLEAR clarification🌹
It is a pleasure, thank you for your comment :)
This is true to a point, he's basically talking about a "droplet mask" where the sieve mechanism only applies. HEPA uses three different principles for function.....interception, impaction and diffusion. In the world of viruses, specifically COVID-19, diffusion is your main friend. Where the air flow through the filter causes the particle (virus) to change into a turbulent movement pattern and adhering to the fibers. So yes, it can filter down to 125 nanometers.
Wow doc what a clear and simple explanation ... I think sometimes we complicate things unnecessarily
😊
At this point, I thank you. I cant rely on the Gov or CDC to tell me what to use bc they cant get their sh!t together.
The government and the CDC have a tough challenge - people are a complex mixture of rational and non-rational reactions, as we all know. Authorities have to balance these - if they are completely rational and ignore “the reactions and fear” of people, they would be accused of fear mongering. In some of my videos (I am a rational PhD scientist) people proclaim I was fear mongering. So the facts sometimes create irrational fear. A nice example is a shark attack on a beach. If an attack happens once every 10 years, people will actually “have a fear to swim”. But, the number of car accidents involving injury is FAR higher than those who are attacked by sharks - but the same feelings of “fear” are not felt. So the CDC and the government have to balance information with “fear mongering”... fear is not a good thing, because it results in irrational behavior, and irrational behavior can lead to unintended terrible consequences. For me personally, I learn, I research, I teach, and I think. I am also in business to feed my family, and hopefully I will create, conceive more inventions, and ultimately bring them to reality. Here on RUclips, with my limited social media skills, If I can bring understanding, I will do it. I appreciate your positive comment Will Brito....
@@bluesky-globaldr.michaelse6427 excellent reason. especially "Fear only hinders." I wanted to learn and research which made me land on your account. Thanks again!
Don’t listen to the CDC they are telling people it’s OK to wear cotton masks which wearing them is better than nothing. But nevertheless you will get sick and catch the virus with a cotton mask this is why I don’t like what CDC is saying
Will I don’t think that is entirely true, honestly putting your arm in front of your face is better then nothing. I don’t think you can catch a virus by wearing a mask
Marvin Cooper true true, but did you hear what joes channel said about the topic?
Thank you, Dr Seitz that answered a lot of questions for me!
You are so welcome! I am thinking of doing more videos explaining things if there is interest
Thank you for the info...makes more sense than N-95 % of what's out there...people obsess over everything...
according to a controlled study, a hepa filter (13? - "conventional" hepa the author wrote = 13?) will filter sars-cov-2 droplets/aerosols by " 85.38%" in 1 pass/cycle of room air, 96.03% after 2nd pass and >99.97% after the 7th pass - how fast for 1 pass depends the air purifier's power
Aaaaaaand the penny drops!!!! I did NOT think of the issue that way and assumed that the virus was smaller than a lot of HEPA filters could capture...
When placing 2 HEPA filters on top of each other would even make it anything but air to cross it. thanks for the assurance.
OK, understandable. So now you got a hepa-filter filled up with saliva and mucus droplets and lots of viruses within those droplets.
As soon as these droplets get caught they undergo rapid evaporation due to the forced air molecules through the filter bumping into the droplets, they evaporate allowing the virus's to break free from the droplets little-by-little and tumble through the hepa-filter netting reintroducing them into the air not attached to any droplets.
Does this sound like an accurate analysis?
rcs300 - yes. That is why I have incorporated UVC filter surface sterilization in my BlueSky Defender machines... to exactly prevent it from happening. Thank you for your comment and observation
The material in the vacuum cleaner bags is called HEPA which is a kind of glass microfibers mat. It is widely used nowadays, you can find it inclusive in your car. The problem with wearing it in a mask can be potentially dangerous since there’s evidence that exposure to glass microfibers increases the risk of respiratory and skin symptoms (as said in the article above).
david williams What is a safe alternative?
You can utilize the filter inside a cloth mask to prevent injury; you wash the cloth for reuse and reinsert the filter
Did you watch the video😂 of course this guys isn’t saying you should wear it as a mask
Melt blown polypropylene ones instead of fiberglass
Dr. Seitz does it mean that nowadays pertains to new normal restaurants or other related events, despite of limiting a number of attendees, one must have HEPA Filters as an added service in the deployment of safety protocols most especially in this type of industry? because the old normal do have air conditioned units to attend customer needs without even thinking the importance of filters but rather focus on a cooling experience to complete the ambiance.
Hi :) this is a good question, and can be answered from various perspectives. From a strictly COVID-19, duct downflow air ventilation with HEPA filtration and UV-C integrated sterilization provides the BEST risk reduction of all methods out there, other than staying at home and never seeing anyone!. Why? Because social distancing only works if people never move. Imagine standing 6 feet from someone with COVID (maybe they don’t know they even are sick yet), they move forward to pay at a checkout, and you walk INTO their space - how did social distancing really help you avoid breathing in contaminated aerosols. SO, continuation ventilation brings clean air in, remove the bad air all the time. Obvious stuff. But the cost of installation falls on the business owner, landlord, etc, and that is a hard pill to swallow. Must easier to say wear a mask or wash your hands.
The next perspective is that of just general smart air - where downflow improves the quantity of air dramatically all year, allergies “vanish” indoors, cold season and Flu season are much less dramatic etc. So a new normal could just be healthy air (the way we now drink bottled water mostly). Blah blah long explanation - point is - clean indoor air should be a new normal, for all sorts of reasons, but will public opinion and buying power force businesses to change and make us all feel really well because the air smells GREAT and clean....
SAMSON SL - yes, bringing in new HEPA filtration and downflow designs with protect people and improve the quality of life for indoor spaces. I am trying to spread the word, including with my own invention in BlueSky, to bring healthy air. Imagine all the people with allergies, or cold or flu season - misery indoors will be significantly reduced.... all it requires is a determination to change and improve designs
@@bluesky-globaldr.michaelse6427 Thank you for this definitely I will share this vid of yours and of course helping to spread the word as well.
Thank you.... if you have any further interests or ideas, feel free to email me at dr.michael.seitz@bluesky-global.com
what happens when the droplet vaporizes and you are still breathing through that HEPA filter?
He is right. Don’t worry about it. In that case, the viruses will die. They cannot survive without our droplet.
Don’t use in masks! They are meant only for use in air filters/purifiers.
Do NOT inhale through air filters. They contain fiberglass & aren’t effective! Please watch.
ruclips.net/video/qiYbXsIcI7E/видео.html
sheeplvl1 HEPA filters specifically are not worn. But generally speaking with filters, and face masks - “dried” residue usually remains trapped on a surface. Let me use a silly but informative example. If dust laden rain drops settle on your car, and dry, the mess on your car would be apparent, and you certainly would not be able to “blow” off the mess. Stuff caught in filters usually stays there by “surface bonding effects” best left for a science class. The practical example on a car being dirty and driving fast NOT cleaning it, is a simple example of “small stuff sticks”
Rich Mc says the 60 year old man starting arguments in a comment section😂
Treebeardshome . So HEPA filters should be banned from use in air recirculating systems? We have those in homes and offices working 24/7 and are breathing in the junk filters put out themselves? I don’t think so.
Covid-19 is a big bigger than 20-30nm. It is 60-140 nm. The droplets were said to be about 500nm. But the filter is also more like a maze than a lattice, so it can still capture individual particles much smaller than 300 nm. [nanometers]
Correct Gary. In my discussion I was referring in that instant to the smallest of the viruses - COVID-19, relatively is a “large” particle virus. And yes, under a microscope, the structure of a filter fabric is a 3D “mat” of fibers, with largely random orientation. For the sake of visualization of the idea of catching something, it is useful to simply concepts. There are a lot more issues to add - for example, once “dirt” gets onto the fabric, the filter improves in filtration efficiency as so on... but in essence, the description as I presented illustrates why a filter with a 0.3um 99.97% specification can be so useful for small viruses since the viruses are actually contained in aerosols. Thanks for your comments Gary
@@bluesky-globaldr.michaelse6427 I also noticed in JAMA, that in real world large study, they didn't find any significant difference in infection of health care worker in Surgical vs N95 masks, although they didn't think it was a failure of the masks. jamanetwork.com/journals/jama/fullarticle/2749214
Garry, it is so dependent on what “study” you read or cite. In a nutshell - it is proven that we expel the virus in mucus/saliva when it sheds. So release and “outward” is clear. It is also well established the leaves an infected person by droplets, with the vast majority in the form of aerosols (
let say the virus is not submerged in mucus or other type of matrix except the air. How significant is the brownian motion effect towards the virus which causes the virus to kind of 'bouncing' around in the air and made its effective radius bigger
Of course there are possible hazards or side hazards when converting a vacuum bag or any other type of HEPA filters into an usable mask for protection. I have built several, but I don't use the HEPA material solely itself. I sandwich it between layers using the pattern: cotton, charcoal, HEPA, charcoal and cotton. Oh btw, the type I build are more of the military style (M17A1) with the screw-in side filter with inflow and outflow valves.
Please, true HEPA filters have a high resistance to air flow - essentially, they are hard to breath through. SO what happens is that when you put on a home made HEPA filter, the air struggles to pass through the dense fabric of the HEPA filter, and BYPASSES air between the mask and your face - simple leakage - because the air wants to find an easy pass. SO unless the mask is physically sealed against your faces, the leakage at the edges will increase (using a dense HEPA) and do LESS good. In a car, or in a machine such as the one BlueSky makes, leakage is prevented by dense rubber seals, and air is forces through the filter. Please, don’t make a HEPA mask, you are going to force more leakage and make the mask less effective. The best combination is good air circulation and air filtration in the public space, and a mask to catch the heavies (cough and sneeze droplets). Hope this information helps... watch my new video to see what system I am suggestion for air cleaning.... follow my channel and share please.
@@bluesky-globaldr.michaelse6427 Uh...Sorry and Hate to inform you, since clearly you have a much better understanding of HEPA filters than my 27 years of military experience and after reverse engineering an actual M17A1 Nuclear, Biological, Chemical (NBC) filter. Also in your hast to criticize, you should've first either study the working of a M17A1 NBC Mask or further invested you time in reading and understanding "Inflow and Outflow valves" But once again typical, quick to criticize without any understanding of the subject at hand...Sounds so familiar of some else.
Michael Angel, if you read my comments, it would become apparent to you that I never reference M17A1 NBC masks - I am pleading with folks wanting to make masks for themselves from vacuum cleaner HEPA filters..... I actually reference engineered masks as OK. Masks without proper face fitting seals that have high efficiency do not work because of leakage.... as you can no doubt confirm, a high quality mask requires a high quality seal, shaved face for men, etc.
Michael Angel , please consider that most folks are not familiar with inflow and outflow valves, Carbon adsorption, etc etc. It is not useful to explain high tech advanced mask making when most folks are fearing infection but don’t have advanced knowledge or any desire to research nuclear, biological and other advanced equipment. So as a closing comment, teaching is valuable, but also remember that 27 years of military experience is an experience you have, but you are one in a few experienced and highly knowledgeable people out there.....
@@bluesky-globaldr.michaelse6427 I post my information on how to properly construct a well fitting mask from using common items which most people throw away everyday. In my videos, I go through several topics (Why a cloth mask is your worst option, but is better than no option at all, Why is cotton used, how and why charcoal is used, Why is a HEPA material used, and how they traps smells, viruses, etc, without using an outflow valved system is both a waste of your time and dangerous, etc.) I also demonstrate how you can use everyday items with slight modification to serve as your both In & Outflow valves, how you can use window adhesive seal (from Walmart) in making an air-tight fitting from the bridge of your nose to below your chin area, I demonstrate how to convert smaller containers into the filters as described in earlier messages and I do all of this for free. Closing: Yes, after building my masks which uses a HEPA material sandwich between charcoal and cotton and from the principles of military's M17A1 protective mask (using your natural inhalation and aspiration of breathing to open and close valves) your breathing isn't as "Free Flowing" as breathing normally, but considering your options of being dead and not breathing at all, most will gladly op for the fore-mentioned. Again, I don't do it for "Likes" or "Money" or "Subscribes" or "Followers" I do if for free, because I'm an American whom served his country proudly, care about those whom I served; this is a time when it's not about the one, but about the all in providing correct information and helping regardless of their color, political opinions, religion, sex or whatever....it's not "Make America Great Again" but "Make America Strong Again", "Make America Heal Again" and "Make America One Again"
Excellent explanation!
Jose Negrete what happens when the droplet vaporizes and you are still breathing through that HEPA filter?
sheeplvl1 virus are too small to be caught simply by a hepa filter, but most viruses are transported through water droplets in the air by a sneeze so wearing a hepa mask definitely does help
@BlueSky-Global, Dr. Michael Seitz hi, can HEPA filter provide better ventilation from spread of covid 19 airborne? tq
Yes…. Absolutely! The key to effective filtration in public spaces is 3 folder:
1. High air exchange rate (12-18 times per hour at least,
2. Air flow direction should be predominantly vertical down flow, so blowing into the space from above, and sucking out at floor level 3. HEPA air filtration to capture aerosols.
This is EXACTLY how air exchange works on commercial aircraft. Building owners/companies are hesitant to implement such systems (my company has full retrofit instal designs) because they don’t want the hassle or the cost of an install. But it is so doable and is the only thing that really makes public spaces safe. More than 2 BILLION people have taken flight since the beginning of the pandemic…. And super spreader events on planes are virtually unheard of. Public spaces should invest for everyone’s future
@@thethatchhouse noted...Thank you Sir for the response..:)
Just a question, since the BSC have consistent airflow, won't the droplets dry out and release the viral particles?
What about he glass fibers in heap filters. Wouldn’t they damage the lungs?
There are hepa filters made with 0 fiberglass
Get the melt blown polypropylene not the fiberglass
Great illustration! However you will not be able to prove it since in HEPA integrity testing we are only looking for 0.3 micron. The criteria would be anything below 0.01% of the up stream challenge of the filter. If you are injection 25,000,000 then the allowable particulate amount would be close 2500 ppm at 0.3 micron. The retention rate would be 99.9900. So anything smaller than 0.3 micron has the opportunity to pass through. Filters are rated for 0.3 micron throughout the industry and the iso criteria for testing is the same. We do not have data to back up anything smaller
Hi and thanks for your explanation. What would be the effect of treating the HEPA filter with a quaternary ammonium compound that binds to the surface of the filter?
Have you got methods of testing it's effectiveness?
HEPA filters can be treated with various treatments or UV…. But in general they do such a good job nothing further is needed
People are using selfmade masks and studies show they work with thick fabric, can i just use t-shirts in the airfilter and wash them regularly?
Unfortunately, this is incorrect explained, yet outcome is the same: HEPA grader materiale after the EN1822 standard (classes h10-h14) Will stop almost everything from 300nm to 0nm due to random brownian motions effect on particulates. So even if isolated virus would float, it would be captured. Please also note, slow airflow across the filter media will increase particle collection effecency and also lower power consumption og fan - yet clean less CFM in a given time interval
Acetylsalesylsyre, you are correct of course, but the specific detail mechanisms are not always required to understand the principles of “capture” - that capturing “encapsulated” or agglomerate particles is different from capturing the constituent particles. I remember a similar analogous discussion - looking at the constituents of table salt - table salt goes well on fries, but the constituents are Sodium and Chlorine - neither of which go well on fries. So the viruses may be small but they are a component of an aerosol - HEPA filtering is looking at the catching the aerosol “VEHICLE”, not the particles within the vehicle.
I thank you for this video, though I have a question. How are the "corona viruses" trapped inside the droplet, since covid19 is an aerosol? Does it create something like a thin air layer or?
The viruses that are shed from the infected person transported within the infected person’s saliva and mucus. Essentially, your entire breathing tract is “wet”. When you breath, or cough, small aerosol droplets are continuously being breathed out. Think of yourself as a “fogging machine” - if your breath against a cold glass (or if you wear glassed with a mask), you will see how “wet” every breath is. In these invisible droplets, it is possible to harbor the dangerous viruses, and for another person to breath them in since they float and are invisible.
@@bluesky-globaldr.michaelse6427 ahhh, thank you
:)
@@bluesky-globaldr.michaelse6427 still a very great video, good to educate people
HEPA works, correct. But what happens when the droplet will eventually evaporate? Will HEPA release the lone virus particles into the air? I think this is the place where UV light comes in.
When that particle evaporates, the virus particles can then pass into your lungs, the droplet that allowed the virus particles to be captured is now gone. Is this why we change out our masks?
So if the water droplets eventually evaporate what do you think happens with the viruses that were in them? After a little research I'm convinced that the virus is much heavier than air as is liquid water. The ability of tiny water droplets to hang in the air indefinitely until they evaporate indicates that they must be expanded with a depressurized core like a vacuum balloon. A preference of water molecules to be in the surface may cause this. If it grows more massive it would collapse into a full liquid state and fall out of the air as rain. If the droplet is buoyant in the air it wouldn't be able to contain many heavy viruses before it would begin to fall like a hot air balloon with too many people in the basket. Bottom line is that gravity plays a major role in keeping transmission rates down by pulling viruses out of the air. But with a virus like covid 19 with a high rate of replication, gravity's work may need some help. Things like inhale filters placed up high with air entering from below and exhale air exiting from a low place would help. Keep in mind that when the water droplets hit the filter they may still evaporate leaving dry viruses which may be stuck between fibers or may pass on through. It's good to keep the flow rate low by using large filter surface area with air flowing up so gravity helps stop the virus passing through.
ruclips.net/video/xcr9eWlj1vQ/видео.html
Wesley, fine particles, aerosols, behave a little differently from rain - as surprising as it may sound before you actually test it, and explain it scientifically (which can be done easily), let me say that under 5um particles floating “indefinitely” - they do not sink down despite being “heavier than air”. Google this to get all the explanations - but here is the important thing.... aerosols WILL float, drifting with the airflow. So if you breath out infected aerosols, and there is NO ventilation and filtering, they will remain airborne and other WILL breathe them in. In the same way a smoker leaves behind the “smoke” in a room with closed windows and no ventilation, the same way we leave behind aerosols. That is why HEPA filtration with good airflow design is so important in combating the spread of Coronavirus.
@@bluesky-globaldr.michaelse6427while quite certain the phenomenon is real, I dismissed the explanations I found for aerosol droplets not falling. One was that the size was too small to be affected by gravity but if the much smaller photon were not affected by gravity then black holes wouldn't be black. The other was insufficient because despite the high ratio of surface area to weight since the droplets are so small it still requires small updrafts to support the droplets weight. This might work for clouds but not fog since the wind would have to be coming out of the ground. It is also unlikely the rising air would be so regulated as to make the droplets not appear to rise or fall. After observing a good deal of time lapse fog videos I concluded that the droplets must be the same density as air. Since the liquid water is heavier than air the only explanation I could imagine is that the droplets are acting as vacuum bubbles. This probably doesn't make a huge difference because even a little air movement will have more effects on the droplets than gravity but I like to be able to visualize what's actually happening. I do think however that the gravitational effect is greater if the droplet is carrying many viruses. This would make them increasingly different from fog or cloud droplets the more viruses they contain. Of course one virus is enough to have a possibility to infect a person.
Wesley, let me try and shed some light on this phenomenon using a simplified explanation - when a particle gets really small, the gravitational force pulling the particle to the ground exists, but is real actively small. At a small enough size this force is low enough that the air “making way” because higher than the downward pull. So think about it this way, the particle is like someone trying to push there way through a crowd.... the crowd being air molecules.... when the particles get small, it simply stays where it is “floating”- like a person unable to push his way though a crowd because they dont have the strength. Now a fun experiment.... take a flashlight with a strongly focused beam, and shine it in a dark room. In the beam you can see floating particles, that don’t fall to the ground but float in the air. Those particles are denser than air, and solid - but there they are floating are moving around like the dance of the fairies. Rays of sunlight through a window will also show all the floating stuff in the air. One final analogy, you can place a very solid heavy brick on loose sand, and despite the brick being much denser (mass per unit volume) than the sand, the brick will rest on the sand and not force its way through the sand. This illustrates that is takes more than gravity and a dense mass to penetrate non-solid substances.... sand is easy to penetrate, but given the right conditions, it can support huge loads.... just the way air can keep aerosols suspended despite them being significantly denser than air.... hope this helps a little
@@bluesky-globaldr.michaelse6427 I appreciate your time to discuss this and hope not to distract you from your mission to help people breathe clean safe air. I just see apples to oranges comparisons when air is 99.9 percent empty space. With these molecules jostling about to maintain their level of heat it seems there can be no static friction so any small constant force should eventually overcome the air resistance. I believe the dry particles in the room are suspended in the air by static charge but I think water is too conductive to hold that level of static in a small space so it seems the vacuum bubble idea is a good explanation for aerosol droplets not falling. Another fact that supports the idea is that light would diffuse through empty bubbles as we see in fog and clouds but would refract through the droplets when filled with liquid water as we see when the sunlight makes rainbows in the rain.
But HEPA filter wokrs for 0.3 micas and bigger particles, so 1 micra can pass thru
That's what I'm saying... 0.1 is smaller than what's filtered so you could still be breathing in hoards of microparticles
Your answer lies in your question...just think..is 0.3 bigger or smaller than 1...hahaha
Dumb...hahaha
@@nicoleboothe9802 medium.com/@bts_50890/breathing-probably-the-most-vital-of-bodily-functions-e48c8f7a116d
It will caught the droplets while they’re moist, what happens when they do dry, released or stuck at that point?
What will happen when the aerosol will dry? Would the viruses be loose then?
Excellent explanation, Thanks
What's stopping the virus from flying away when the water that suspends it evaporates?
By then it’s alrdy desegregated...they die and rote away like us too
@@trifilosgr You're saying the virus is killed in a few seconds, or minutes at most? Then there's no real need for masks.
I am guessing this is why RH is very important as well. Dryer air has less water or smaller diameter raisin buns?
Yes... but I think the reasons related to humidity are different. Please watch some of my other videos to see an explanation regarding humidity...
The HEPA filters should also have UV-C light.
Open areas should have 222 nm ultraviolet light. The most vulnerable should have it in their HVAC systems. Most homes have ultraviolet light in their HVAC already. Nursing homes need at the most. The far UV- C should be in supermarkets, factories, schools, etc.
Great explanation. Thank you so much!
Thank you, doctor, this is very helpful for my research
but what happens when the droplet that's been captured by HEPA filter dries over time? wouldn't that blow virus particles into the air?
This explanation also assumes that the droplets that envelope the virus particles stay intact when passing through the filter. If the filter actually causes the droplets to break apart, it could be making the problem worse rather than better.
Do mask also capture these droplets? If yes then why wud someone need hepa filter masks so expensive?
I added a video to explain how HEPA filtration can be used to protect us - ruclips.net/video/kWV2myIc3tM/видео.html
Could you please explain then why breath with water content still makes its way through several layers of mask or hepa? Does hepa stop 1 micron particles?
What happens when the h2o in the saliva eventually evaporates? Will the vírion become mobile again within the net/filter?
Potentially, but the formites on the filter surfaces most likely will remain “attached”. The BlueSky Defender machine which I invented which uses HEPA filtration, has a built in UVC radiation source within 2 inches of the filter surfaces to destroy ANY captured viruses. The most important design consideration I used is the UVC light need exposure time to act, and the potential viruses within the HEPA filter “fabric” will be neutralized effectively. Killing viruses in free flow air within air ducts is totally useless in my opinion, but radiating surfaces for longer periods is an excellent method of destroying pathogens
skip to 2:50 summary.
Excellent explanation sir
Sir without any doubt we can use hepa filter to get virus free air????
Nikky, 100% is actually never required.... we strive for 100% of course. For coronavirus, this key is to reduce the loading (concentration) of viruses in the air. For machines like BlueSky Defender (my invention) the concept is to significantly reduce the aerosol (and all the bad stuff in general like allergens) to levels that are very low. The biggest danger we face at present in most indoor spaces is that clean air ventilation is very low in the winter and summer months if air conditioning is present. In public spaces, I always recommend at least 12 room changes an hour, with HEPA filtration of the circulated air. Spaces with such ventilation are MUCH safer....
Thank you sir for your valuable explanation
These words clarification my doubts
Thank you sir
Can you tell me how important a refresh rate is inside the airplane with a HEPA filter? Or is refresh rate not a factor?
01 s o n g s - refresh rate is very very important, because it reduces concentration. So think about it this way... if people are smoking in a closed room, the concentration of smoke would build up quickly and become choking quite quickly. But if you opened a window, some of that smoke would drift out, and improve matters. Open two window on the opposite sides of each other, and create a strong cross draft (maybe windy outside), and you would remove the smoke much more quickly and the concentration would no build up. Smoke are “aerosols” - we see and smell that - with breathed out aerosols they are “invisible”, but still behave exactly like cigarette or cigar smoke....
Good explanation ! However, that means one can therefore indeed use almost any material, such as coffee filter paper etc, as a mask, since these will surely catch mucus droplets..
Maaifoedie De La Rey yes, however the higher the efficiency of filter, the large amount of particle that can be captured
Maaifoedie De La Rey - HEPA filters are used in “machines” as a very effective filters of the highest quality we can currently manufacture in volume. I think one of the misconceptions is that HEPA is intended for breathing masks - HEPA is intended for filtration systems for spaces where pollutants and pathogens are present - for example a plane, a hospital, and even modern cars. For the currently challenges we face, I am strongly suggesting in my work that HEPA filtration systems be installed in large public spaces, so that the air WE ALL HAVE TO BREATH when we are in these public spaces are a “clean” as possible. In the same way, we want the water coming out of our facets, the food we buy at a store, to be clean. It has always amazed me how conscientious we are above safety, but he air we breath is often “not great:. HEPA filtration in public places goes a long way to improve the situation, and reducing health risks...
It is aerosol. So, now what? Will it still work?
According to Wikipedia, the coronavirus is around 0.1 micron in the diameter.
There are various size estimates, all in that “range”. However, the individual size is not as relevant as the viruses are shed and expelled in mucus and saliva, and these particles are much bigger. In essence, filtration captures the “transport vessels” containing the individual virus particles
Thank you Doctor Seitz. :)
You are welcome. I made another video to dive into some of the aspects affecting virus transmission... ruclips.net/video/MQ-gyjoDFts/видео.html If you like it, I will continue to make more of this kind of video :)
Can virus flout in air individually? without settling on particle?
I believe that the person in this video who is explaining about the HEPA filter at what microns does it filter out viruses I believe he is wrong on the microns that HEPA filter does filter out. If it is authentic five layer HEPA filter then it will filter out the same as N 95 mask which is 0.3 µm so I don’t know why this gentleman is saying that HEPA filter only filters 1 µm which is not true because it filters 0.3 µm
Etihad Airways just placed HEPA filters into their aircrafts.
Smart, they should all do that
I have heard that HEPA filters are made fro glass micro-fibers. Wouldn't you breathe it in when wearing the mask?
Most hepa filters are not made of glass microfibers, they are made of a polyester type materials, depends on the type.
@@leslielawrence7941 Thank you, I was very hesitant to use it in making masks for my family members.
Don’t use in masks! Only in air filters/purifiers.
Do NOT inhale through air filters. They contain fiberglass & aren’t effective! Please watch.
ruclips.net/video/qiYbXsIcI7E/видео.html
Angie Corona Please DONOT make HEPA filter masks.... HEPA filters are used in machines like we make at BlueSky for large public spaces. They are not useful for people, and no HEPA filters masks can be bought - they can’t be breathed through. If someone offers you such a mask, it is fake... or if it is a real HEPA laminate Fabric, you will not be able to breathe through it normally.
@@leslielawrence7941 Thanks for the heads up
So I have a small office. Should I have the filter pointed at me or behind me?
This is an interesting question, and is highly subject. Objectively, I would say that “ductless” systems have limited value in public places. However, if one is used, the best location would be on the side of the desk others sit - you don’t really want to draw air others have breathed out over yourself toward a machine placed behind you. But again, in my opinion and based on flow dynamics (I am an engineer) the only truly effective solution to safe air is downflow ventilation with HEPA filtration of the return air. I have dedicated my life at this time to try and educate on this topic, and also provide equipment that can serve in the role (my company BlueSky-global has developed such large machines for placement in large offices, call centers, waiting rooms, and retail lineup areas where cross infection risk is highest).
thanks, I needed that ;) God Bless you! †
People are wearing masks that are three layers of cotton. Thinking that those are filtering out particles When you inhale? And Exhale? So .... What's your feeling about ever flow personal filtration devices that filter air before it enters your mask. They're using a HEPA filter with charcoal in it to filter the air before it enters your mask. What's something like this filtrate the Coronavirus applied to an n95 mask or cotton mask three layers thick?would think I could just use three layers of cotton in there. Or I could cut up n95 mask and make a bunch of filters out of it for a device that filters air
Flaming Polish Hillbilly - masks are an essential primary protection we take personal responsibility for. I suggest a basic mask is better than no mask. In essence through, I feel that without proper indoor ventilation (as I have spoken about at length on my other videos) there will be continued major cross infection.
this vid going get some more views
Thank you... understanding technology and how things work can be important when trying to understand options and choices
Louis-Philippe Lavoie - what topics do you think would be of interest to folks, specifically related to the virus?
what happens when the mucous evaporates from the fan and all those viruses are dispersed out?
That is a good question - and not easily answered. The “dry” mess is still a collection of particles (stuff). I think it is sufficient to say that we should be most concerned with “fresh concentrations” of aerosols in stagnant air. There are many mechanisms where, say, captured aerosols in HEPA filters kinda “stick and stay”, rather than “wiggling their way” out. In general, at the micro level, filters work in a multitude of way to catch and hold very small particles. To me the most pressing question is “why is there not more emphasis on air ventilation in public spaces”. Any ideas, anyone?
Well explained Thanks Doctor
You are welcome :)
Ohhhhhhhhh that actually makes a lot more sense, so in theory if someone wore a true hepa filter face mask and they had a virus would other people be ok?
Dr. Seitz is referring to machines with HEPA filters not masks with HEPA filters as air can flow out through the side of the mask
Just a little FYI good points and he’s not saying to use it as a mask. Plz DONT 😂
Why not?
Marc Isaacs ok boomer jk just go do some research or ask this guy and I’m sure they will tell you quickly
@@saltymat2052 u clearly had no clue. medicine.uiowa.edu/iowaprotocols/n95-respirators-hepa-or-high-efficiency-particulate-air-filter-respirators-personal-protective
@home media 😬 for you because you are going to spend all that time adding a HEPA filter to your mask with out realizing that the air will just travel through the sides instead. Once again plz don’t thank you:)
@@saltymat2052 do you have research evidence? Doctors have used hepa respiratory mask(pre cov!19). It's in article I linked.
Do you have any proof I can work with? What is this "research" you speak of? Comparable to uiowa medicine?
Please Subscribe - I will make some informative videos on this subject in the future....
CAN WE combine IT WHIT UV LIGHT 👈 🙏🙏🙏
No
@@cjadventures8840 oooh SO SAD FOR you... THEY DID 😂
Our Meaco air purifier has a UV lamp in it to kill viruses.
Hello, and how about Omicron? Will a Hepa 14 Filter do the job? Greetings:)
Absolutely…. If the air flow is sufficient (say 18 room changes per hour), and the flow direction is from above to floor predominantly, together with HEPA filtration, the risk of cross infection is HUGELY reduced
@@bluesky-globaldr.michaelse6427 Oh, thank you. Yes, 18 complete air-cleanings of the entire room within one hour (= one complete room cleaning in 3,3 minutes:). On highest mode...and it´s Hepa 14. The Filter sucks the air in at its bottom and releases it vertically towards the ceiling. And my daughter (7) would sit on one side of the filter, and me on the other - at least most of the time. So I can´t infect her(that´s my big worry). Because I saw how the virus can make even children very ill. What´d be your opinion? Thank you for answereing. Good health to you and your family:-)
@@benstiller500 The flow is not quite as you describe. The air is “pushed” from above, and sucked in from the floor area. So top to bottom. Like on a commercial plane. If you go to this web link there is a picture to show you… let me find it and paste it in a reply to you
@@thethatchhouse ruclips.net/video/BajUci7Em_k/видео.html
Why don't waltnart drs practices
👌
Then sew a fabric cover for these to eliminate that problem.
wow exelente explain 👏👏👏👏
Thank you...
Hi everyone, I made another “explaining stuff” video relating to the virus and seasonality ... check it out and let me know if you would like to see me make more ruclips.net/video/MQ-gyjoDFts/видео.html
Use DFS technology that can filter 0.007microns
Hi Sarah... using technology that can filter such small particles is of very little value. The particles that we need to “not breathe in” are typically larger than 0.3 microns and up. The reason I say that is that individual virus particles (as those we see in virus depictions and diagrams) are really not real - the method of transfer from an infected person is in mucus and saliva, so as I tried to explain, like a raisin bun. Let me ask you, why did you endorse the 0.007 micron idea?
was the beginning scripted... lol
thank you
SAMSON SL, your are welcome, thank you for commenting. If you have any more questions or interest, you are welcome to contact me directly...
Please... thank you for your comment...
IFD FILTER
HEPA masks.... I made a short video specifically on this topic.... please share, and follow me if you are interested in Aerosol spread science and novel thinking regarding “what may be happening” ruclips.net/video/DIYIAErKtAo/видео.html
Hi all, I have published a new video on how I believe we can prepare for a potential second wave of the Coronavirus. Please watch and share ruclips.net/video/x7wqZK2wIpA/видео.html
THIS VIDEO IS TRYING TO CAPITALIZE ON YOUR FEARS AND IT COULD KILL
Scott, not sure how you draw your conclusion, but having an understanding of how things may work, it always useful. Disagreeing with an explanation is certainly part of a good discussion, but linking ideas automatically to “huge danger” may be a little too dramatic. Would be interested though in your thoughts on virus transmission mechanisms, and how to limit spread...
Hi I just posted a new video on seasonality! if you enjoyed this video take a look at this one as well ruclips.net/video/Vfb-u7dPYY4/видео.html
BS !!!
?
@@bluesky-globaldr.michaelse6427 I worked in Hazmat and was Lic . Only Full SCUBA can protect You from Viruses ! And only if the air tank air is clean of viruses !
John, it is time to be pragmatic - reducing concentrations of viruses is the critical factor. It has been extensively shown that with low concentrations of aerosols, the risks of contracting Coronavirus is hugely diminished. Think of this analogy - as crude as it may be - if a couple is trying to fall pregnant, and the man has low sperm cell count, it is very tough (but possible) to fall pregnant. In the same way, a room that has 12 room changes of air per hour of HEPA filtered air is MUCH safer than a room with minimal ventilation and no HEPA filtration. We need need to shoot for perfect, we need to shoot for low concentrations that are MUCH safer....
@@bluesky-globaldr.michaelse6427 This Corona Madness is just that madness ! Only SCUBA will work, and only if the air tank is virus free ! Get rid of the masks and let Your immune system work !
John - some people do not have that option because they have compromised immune systems and other complications. We are trying to protect the elderly - those folks we can thank for being moms and dads, and citizens who also deserve care. If we have outbreaks (waves) that exceed hospital capacities, such as those in Italy for example, we are face with triage, and frankly, that is terrible. Imagine your own parents potentially struggling to breath and facing a terrible end-of-life experience. Perhaps it is better to take better care of the air quality?