Do More Ultra-Long-Haul Flights Pose Higher Radiation Risks?

With the constant push for more, and longer, long-haul flights, pilots and other aircraft crew are possibly at risk for increased levels of radiation.

In fact, airline employees are among the most susceptible groups for work-related radiation exposure. They have higher levels of hazardous exposure than radiology workers or even nuclear power plant engineers, according to research from National Council on Radiation Protection and Measurements.

The increasing number of ultra long-haul and polar routes might be worsening this exposure, a report from Bloomberg says.

The amount of radiation per extra-long-haul flight is about equal to one x-ray. That's because at a higher altitude, the layers of atmosphere that protect us from radiation at ground-level are thinner. This radiation exposure is stronger at the Earth's poles because of the planet's magnetic field, which acts as a shield against radiation, is weaker there.

So, longer flights, and especially flights that cross the south and north poles, carry a higher potential for exposure to harmful radiation.

Polar routes have become more common in recent years, according to Condé Nast Traveler. Commercial flights have been flying over the Arctic and the north pole since the 1950s, but newer, more fuel efficient aircraft, increased access to airspaces that were previously closed, like the former Soviet Union's, and higher demand for international routes have made transpolar flights ever more popular.

Advances in modern aircraft also make longer and longer routes increasingly possible. This year Singapore Airlines, for instance, will re-start its 19-hour nonstop route from Singapore to New York, suspended in 2013 when the Airbus A340 used on it proved to be too expensive because of its four engines. With the arrival of the new A350, which has just two engines and even longer range, Singapore will regain the title of world's longest flight from Qantas, which will take it in a few weeks with a Perth - London nonstop on the Boeing 787-9.

Last year, United launched the longest flight ever by a US airline, its nearly 18-hour service from Los Angeles (LAX) to Singapore (SIN). Qatar Airways' long-haul route from Auckland, New Zealand (AKL) to Doha, Qatar (DOH) also launched in 2017 is just behind United, clocking in at 17 hours and 30 minutes. Also on the horizon might be Qantas Airways nonstop routes from Sydney (SYD) to London and New York by 2022. The idea is part of Qantas' "Project Sunrise" and would require a jet capable of flying 20 hours straight, which no current model could without extensive modifications.

"There is no way you can be a pilot and not get this exposure," Mike Holland, a captain for American Airlines and a radiation expert for the Allied Pilots Association, told Bloomberg. "In our job, we're going to get this exposure."

Also potentially at risk? Frequent fliers. If you're a passenger logging many long-haul flights, radiation exposure might be worth taking under consideration. The Bloomberg report cites the most extreme example of a plane flying over a pole in a solar storm, which would mean exposure of up to 10 milliSieverts, or about three years of natural background radiation.

Some airline employee groups say it's difficult to get airlines to focus on the issue, especially when these routes cut down time and save fuel, increasing profit. "It’s been difficult to get traction," Judith Anderson of Association of Flight Attendants-CWA, told Bloomberg. "The nature of the hazard is invisible, so it’s easier to forget about and get attention for something more pressing."