How long do cough droplets take to settle in a bathroom?

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If anyone coughs or sneezes into a bathroom and spreads virus/bacteria. How long before such droplets settle to the floor or wall. Is there a standard calculation of it like based on velocity, weight and ambient air in the bathroom?
 

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berkeman said:
It's pretty quick, just like if you used a spray bottle.

Why do you ask?

Someone in the house has cough from ordinary colds (since 4 days ago). So whenever the person enters the bathroom. I was waiting how long to enter it and not sneeze in the droplets. Sometimes I just hold my breath.
 
If someone has an active cold for 4 days, it is very likely not the common cold - first off Consider: Allergies, all kinds of other "cold" like virus diseases. Allergies no problem, I guess.

Anything else, WASH your hands. Hard surfaces like door knobs, faucets, handles, kitchen/bathroom sinks, etc can harbor active virus for 8-24 hours post sneeze, longer for some other kinds of surfaces, shorter for bare skin.

Your only defense is to wash your hands, keep your fingers out of your nose, eyes, and mouth to limit transmission. Your evasion plan will not work longterm. You need more. And yes, transmssion from airborne droplets can occur, not that often. If the person sneezed into your face in front of you then this is a sure fire method to transmit flu and cold. This is why small children are a primary vector for flu.

There is a reason every medical exam room has both a bottle or dispenser of hand sanitizer and a sink with antibacterial hand soap. Clean hands do not infect.
 
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new6ton said:
Someone in the house has cough from ordinary colds (since 4 days ago). So whenever the person enters the bathroom. I was waiting how long to enter it and not sneeze in the droplets. Sometimes I just hold my breath.
You could request the person cover their mouth with a handkerchief when they sneeze or cough.

At work we always say, "please don't give it to me," as a hint.

Can you get a flu jab where you are? You can get this free if you have asthma in the UK
 
There really isn't a set amount of time that droplets stay suspended, because droplets from coughing and sneezing can vary greatly in size, and the smallest "can stay suspended indefinitely" depending on simple air currents in the location (https://www.livescience.com/3686-gross-science-cough-sneeze.html)

Additionally, a really big thing to watch is how surfaces get touched, and where commonly touched surfaces are. As particles settle onto a surface that gets touched, further touches keep spreading those particles further and further. Door handles are among many objects that really help spread various things around a community (https://www.cbsnews.com/news/one-germy-doorknob-can-infect-half-your-office-within-hours/)

But, one positive take away from this - you've likely already been exposed to those specific germs. You're currently not sick from them from what I understand you've said, so you probably either have a subclinical infection or are not likely to become infected. So, use the restroom as you choose, perhaps?
 
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