The fear behind the rule of ‘no phones on planes’ is that portable electronic devices could potentially interfere via electromagnetic radiation with the measurement and navigation tools on board. Modern planes, however, are built incredibly resistant to electromagnetic radiation, they can actually withstand a lightning strike without instrument problems, and so the small amounts of radiation from your devices aren’t likely to bring down the plane.
It’s time to put to rest the idea that plane air will make you sick. While the thought makes sense, as the air on a plane is indeed recycled, and the many passengers are spreading their germs into it, this misconception forgets one major part of plane’s ventilation system- HEPA filters. These filters are the same ones trusted to keep hospital surgical units clean, and plane air is re-circulated, and therefore re-filtered 20-30 times per hour. It’s also important to remember that only about 50% of air on a plane is recycled. The other half comes from outside, and enters the plane through the engine compressors. The true risk of getting sick on a plane comes from the close proximity to other people that flyers find themselves in while airborne. This risk, however, is the same as what one may in a lecture, at a party or on the bus.