Having been born in a place where people don't habitually chat with strangers in line at the pharmacy/the grocery store/the DMV, I still find it unsettling when this happens to me in California, despite having lived here for 20 years. And now there is public health advice, from experts, confirming that this unnecessary chit-chat can actually be deadly, so I'm sharing it.

It should be widely understood by now that the SARS CoV-2 virus is easily aerosolized and can be spread, airborne, in indoor spaces. This is why airplanes remain scary, and why we won't be dining indoors at a restaurant anytime in the near future in San Francisco.

Face masks shield us from some of these aerosolized droplets on which the virus travels, however they do not protect us 100 percent. One piece of public health guidance that hasn't gotten enough airplay is that talking — particularly loud talking, and also singing — is especially effective at creating and spreading more droplets, and total silence is the safest way to conduct oneself in an enclosed space.

"Every route of viral transmission would go down if we talked less, or talked less loudly, in public spaces," says University of Colorado Professor Jose L. Jimenez, speaking to The Atlantic this week. "This is just a very clear fact. It’s not controversial." Jimenez goes so far as to say that if everyone in America would just stop talking for a month or two, disease transmission would drop to next to nothing.

Also, quiet talking or whispering "reduces aerosols by a factor of five" he says, and "being completely silent reduces them by a factor of about 50."

Jimenez suggests that movie theaters, while not without risks based on how well ventilated they are, "don’t seem nearly as dangerous as a loud restaurant or bar, where people have to speak loudly to be heard." Gyms, on the other hand, don't score well with this metric according to one recent study that suggests that people exhale far more droplets than normal after a heavy workout even while talking normally, and a whole lot of aerosols get produced through heavy breathing during a workout.

And what about hairstylists who traditionally are the chattiest of the chatty, standing over clients all day — can they ever be encouraged to zip it?

Do I need to remind you about the Washington State case from March in which three-quarters of choir members got sick after one socially distanced practice that lasted two hours in an enclosed space? Singing indoors is clearly a risk factor too.

Donald K. Milton, a professor at the University of Maryland School of Public Health who has studied the effectiveness of masks, agrees with Jimenez, saying that "silence and quiet speaking are reasonable means of intervening" in slowing the spread of the virus. And to prove the point, this recent study of the effectiveness of different mask types gauged droplet-emissions by having participants simply speak a phrase through the mask.

And public transit agencies may want to take a cue from Japan, which has done well to reduce the spread of the virus by telling everyone to avoid "close-range conversations," in addition to crowded spaces and closed spaces.

SFMTA Director Jeffrey Tumlin tweeted out a link to the Atlantic story today, adding a photo of a sticker that's existed for many years inside Muni buses that says, with regard to bus drivers, "Information gladly given but safety requires avoiding unnecessary conversation."

The writer behind the Atlantic piece, Derek Thompson, suggests that library rules ought to apply for the duration of the pandemic, anywhere in public. "Every time you walked into a school, a medical clinic, a drug store, a barbershop, an office, an airplane, a train, or a government building, you should see a sign that read: HUSH FOR YOUR HEALTH; or MAKE GOOD CHOICES, LOWER YOUR VOICES!; or KEEP QUIET AND CARRY ON," he writes.

Hear hear! Maybe we can eventually reopen bars and restaurants, with mask rules, if people stay distanced and not talk to people at other tables — but this may be too tall an order for chatty Californians, not to mention drunken bar-goers everywhere. Some of us go out to social spaces in order to have unnecessary conversations, and herein lies the trouble. The pandemic has stripped us of so much that we enjoy in life, do we have to give up idle banter too? Is it reasonable to think that people who are culturally conditioned to commiserate with each other in line at Walgreens will be obedient if there's a sign telling them to shut the fuck up?

Probably not, but I for one could always do without small talk in places where small talk is not what anyone came there for. Until we do get to go to bars again, keep it to yourself at the deli counter or dry cleaner. None of need your extra droplets.

Photo: Getty Images