Experts on speech and language have (with tongue positioned somewhat in cheek) been examining how the way we talk can help cut down the risk of spreading droplets.
It is well known that a cough or sneeze can violently project these out of the mouth, but it also happens to a lesser extent during speech, especially if you use a lot of consonants, the researchers say.
This is especially the case for the ‘plosive’ consonants, such as ‘b’ and ‘p’ explains a linguist from Aix-Marseille University, Médéric Gasquet-Cyrus, in a video made for France Bleu Provence.
This is because contrary to vowels, where the sound is made in the throat and comes out of the mouth or nose without obstruction, in these sounds the lips block the airflow and then it is pushed out again with additional force.
The speech of the typical Marseille resident is notably risky says Dr Gasquet-Cyrus, as it typically involves copious use of words such as putain! [popular swear word meaning ‘prostitute’].
Hence saying something like “Putain! C’est pas possible!” [roughly, "oh for ****’s sake"], is especially dangerous, he explains.
Rather than this word you should go for more polite options, like flute or even better zut, which obstruct the air less violently, he says.
You should also in general avoid insulting people and speaking too loudly, he advises.
Speaking gently has also been recommended by an American team from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), who used a laser to pick up on the number of droplets expelled into the air by repeating the phrase ‘stay healthy’ in a loud voice.
They found that speaking loudly could generate 1,000 droplets per minute, which could stay suspended in the air for at least eight minutes in an enclosed space.
“We noticed that the number of laser flashes increased with the intensity of the speech,” the researchers said.
A linguistics professor from Paris Diderot University, Philippe Martin, told news website BFMTV.com that another factor with consonants is that those which create vibration in the vocal chords are less likely to expel air violently than those which do not (because the vocal chord vibration slows down the air).
“Saying ‘Papa’ or ‘Tata’ [Daddy or Aunty] would seem to be particularly dangerous,” he said.
“We can’t speak without expelling air, but ‘pa’, ‘ta’ and ‘ka’ use voiceless occlusives [consonants formed by creating a brief block of airflow in the vocal tract; also called ‘stops’]. It’s like if you burst a little ball. We therefore expel a lot of air.
“Their voiced cousins, which make the vocal chords vibrate, ‘da’, ‘ga’ and ‘ba’, are similar but expel less air and so they don’t carry as far.”
Fricatives, consonants made by forcing air through a narrowed channel such as tongue against teeth or the soft palate, can also cause problems, said Dr Martin. However again the voiceless fricatives like ‘f’, ‘s’ or ‘ch’ are worse than the voiced ones, ‘v’, ‘z’ and ‘j’.
This explains why words like tu, toi and te, which use voiceless stops, are worse than vous and votre etc… which use a voiced fricative.
“It’s become a joke among researchers at the CNRS,” Dr Martin said. “We’ve been saying we’re going to stop calling each other ‘tu’ and go back to using ‘vous’ so as to avoid the occlusives. Some even said we must ban all the consonants from the French language.”
Did you know?
The French word postillon, referring to the droplets of salivathat can come out of the mouth during speech, originally meant the driver of a post carriage and has several related meanings including, in old-fashioned slang, a small lump of bread containing a message inside used the pass messages inside prisons.
According to the CNRTL national linguistic centre the meaning ‘droplet of saliva’ may have come from the fact that post drivers were considered unrefined, or may be linked to the lump of bread term.