It happens moments before take-off once holidaymakers are buckled into their seats and ready for the hours-long journey home.
Not on every flight, but from certain holiday destinations, flight attendants walk up and down the plane’s aisles and spray a liquid over passengers’ heads.
Many passengers are left wondering what it is that they’re spraying into the air within the confined space and whether it’s dangerous to inhale.
It can be a confusing experience if you don’t know what’s going on, but this explainer from the Manchester Evening News will fill you in.
The process is known as disinsection and is required on flights to and from certain destinations to prevent infectious and contagious diseases, a Civil Aviation Authority spokesman said.
It’s mainly sprayed in countries where diseases such as malaria and yellow fever are spread by insects, including mosquitoes.
The World Health Organisation has a set of guidelines outlining when and where it is necessary.
Which countries are affected?
There are a range of countries, such as Cuba, Jamaica, India, Australia and New Zealand, where the aircraft is routinely disinsected before take off.
The World Health Organisation website says: “There have been a number of cases of malaria affecting individuals who live or work in the vicinity of airports in countries where malaria is not present, thought to be due to the escape of malaria-carrying mosquitoes transported on aircraft.
“Some countries, e.g. Australia and New Zealand, routinely carry out disinsection to prevent the inadvertent introduction of species that may harm their agriculture.”
Planes are sprayed in countries where diseases are spread by insects
In 2012, there was a Dengue outbreak in Madeira – the first outbreak of such disease since the 1920s.
What is the procedure used to disinsect the aircraft?
There are three procedures that are used to disinsect the aircraft listed on the World Health Organisation website.
They include
1. Treatment of the interior of the cabin using an insecticide spray just before take-off.
2. A spray of the interior of the aircraft before passengers get on board using a residual-insecticide aerosol, as well as inflight treatment with a spray before landing.
3. Regular application of a residual insecticide to all internal surfaces of the aircraft, except food preparation areas.
Is it dangerous?
The website says that the spray poses no risk to health, despite passengers sometimes complaining of feeling ill after it’s sprayed.
It states: “Passengers are sometimes concerned about their exposure to insecticide sprays during air travel, and some have reported feeling unwell after spraying of aircraft for disinsection.
“However, WHO has found no evidence that the specified insecticide sprays are harmful to human health when used as recommended.”
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