Nose-blowing

While nose-blowing helps to alleviate symptoms of the common cold and hayfever, when it is done excessively or incorrectly it may bring potential adverse health effects.

[4][5] In a 2000 study, doctors squirted dense liquid dye, which could be seen on x-rays, into the noses of several adult volunteers.

It was found that the typical pressure of nose-blowing was 1.3 pounds per square inch, ten times greater than that generated by sneezing or coughing.

[8] Nose-blowing becomes a breach of etiquette in most cultures if it is performed directly in front of someone at a dining table or in a lobby.

It is also considered rude to continuously snort mucus back into the nose instead of blowing it.