Pandemic science, Talk quietly please

Aerosol emission and superemission during human speech increase with voice loudness (Nature Scientific Reports)

Coughing and sneezing, visible droplets + small ones

Visible, 50 micrometres upwards

Normal speech, just the small ones

One micrometre, invisible

Carry a variety of communicable respiratory pathogens

Particle emission during normal human speech, positively correlated with the loudness (amplitude)

Quite, low amplitude = 1 to 50 particles per second

Loud, high amplitude = 10 to 500 particles per second

Regardless of the language spoken (English, Spanish, Mandarin, or Arabic)

Counting aloud from 1 to 100 releases at least 6 times as many particles as an individual cough

Singing, x 6 compared to normal speech

Speech superemitters

x 10

Small particles

Suspend in the air

Penetrate deeper

Applications

Normal speech 10 decibel range

Ambient noise in restaurants, 70 decibels

Quite zones in public spaces

[paolajaramillo]

I really like you Dr. Campbell, I have no words to express my gratitude for your job during this difficult time 🇪🇨🤗

[m.c.]

Thank you Dr. John, don't know how you do it, but I'm here everyday. Thank you so very much for all the information, thoughts, and science of course. Best to you sir.

[cd]

Thank you for all your hard work especially the review of research papers, if individuals went to your research links themselves., most would be left bewildered just trying to comprehend the content, thank you for putting it all in layman's term's ' . Well done .

[suewright]

I just love your type of humour amidst all your very serious videos Dr John. You're a lovely gent I love listening to and giggling at (in a nice way) and ssshh quietly! 🤫 Many thanks for another great video.

[GerbenWulff]

Background noise also makes people keep less distance so they can hear what others are saying to them.

[suzann]

In that case why aren’t MPS Wearing masks in Parliament

[paulavandenbroeck]

You never know - listening could become a thing again!

[dpbreger]

Thank you. For your knowledge, intelligence, and kind heart... Thank you for addressing the children. Please keep with us all. May you and yours forever be well.

[mjwilliamsb]

what a brave man you are Dr. Campbell - unfortunately, as word about your brilliant informative videos has spread, you've acquired a coterie of, hmm, what's a non inflammatory term that does not involve swearing, let me think .... nutters will have to do, though I can readily think of several more pithy terms- this video and the one on vaccines has brought them out in force I'm sorry to see... I, along with many others, heartily appreciate every bit of research and information you put out, been watching you since January, a calm voice of sanity in difficult times.

[Vierotchka]

Some people do emit a lot of droplets when they talk normally, some quite large, and these larger droplets are quite visible and one feels them when they land on one's face.

[trapper]

I never actually thought about this but it makes perfect sense thank you Dr John

[theamazingtif]

If I’m in a shop and have to pass someone speaking, I hold my breath as I pass. I know it sounds silly but it seems like an easy thing to do to minimize the risk.

[deathcar]

Thats why Bars are such great spreader places, start drinking and TALKING LOUDLY, then everyone around you has to do the same...especially in the indoor settings. My city has had close to 300 outbreaks and as far as I can tell the vast majority (if not all)were indoors...this is quite astounding considering I live in a year around beach town.

[RussellChapman]

2m distance and talk quietly through a mask, by the end of this people will be conditioned to never approach or say even a hello to a stranger ever again. I'm not saying we shouldn't be sensible, but long term social distancing seems more like social fragmentation to me.

[JosephFallon]

I can tell you enjoyed that one Dr C.
I said WE CAN TELL THAT YOU ENJOYED THAT ONE DR. C

[tommyzz]

Well said Dr. John: "I hate ambient music (in restaurants)...but i love music when i want to hear it." My thoughts exactly. Especially clothiers and department stores.

[Erict]

I've been saying this forever. It seems so obvious. I tried to avoid loud people. I really wouldn't be surprised if super spreaders are really just super extroverted, noisy folks

[CCRmusicfan]

Yes I noticed that. Got it awhile ago. I find it ironic that those who don't want to wear a mask shout the loudest

[luciarixon]

Thank you for all you do . I've been following you for a long time and today's subject hit home. I agree with all that you said but I am feeling victimized by covid 19 restrictions I am hard of hearing and now with masks I can no longer rely on lip reading and surely I am not alone in this. Now you ask people to talk softly Help! It is a problem I am in my late sixties and find many times that people do not enunciate cleanly and some run their words together as they try to talk too fast. As it is I avoid crowded places or those that have music or machinery operating in the background. I feel for those that are far more hearing impaired than me so sad to miss a whole world of expression in facial features . For so many small minorities this time is so hard in many different ways. So people as you cope with the current situation give some thought as to how it maybe affecting others and you'll be thankful of your abilities to cope . Live long and prosper 😆

[OldDeanKenobi]

Talking quietly with a mask = pardon I cannot hear you & say again, didn't catch that + what?!?!