Epilepsy and Strobe Flashes
300,000 people in the United States that suffer Epilepsy when exposed to flashing lights or to certain visual patterns that can trigger seizures. This condition is known as photosensitive epilepsy.
The photosensitive epilepsy becomes less frequent with age and usually disappears in the twenties. People without epilepsy are disturbed by light exposure do not develop seizures but experience other symptoms like headaches,nausea, dizziness and other debilitating effects.
People who experience seizures are unaware they are sensitive to flickering lights or to certain kinds of patterns. These people may never go on to develop epilepsy, which is characterized by recurrent spontaneous seizures, though a seizure may be triggered by certain photo-light conditions.
Television screen flickering, computer monitors that flicker, certain video games and TV broadcasts that contain rapid flashes or alternating patterns of different colors and intense strobe lights that may cause seizures in photosensitive people.
It is the latter cause, strobe lights, that concerns pilots and their passengers in private planes. Frequency of the flashing strobe, its brightness, wavelength and visibility surrounding the plane at the time of the strobe operation are important possible triggers. If you are concerned about photosensitivity and are not epileptic ask your doctor about ordering an electroencephalogram (EEG) to test your brains electrical activity under various conditions including light stimulation produced by strobes positioned in front of your eyes. An abnormal response may indicate the presence of photosensitivity.
If you are photosensitive and you want to avoid the effects brought on by strobe light exposure you can cover one eye and turn away from the light source. This is difficult in a plane. A much easier solution is turning off the strobe light system for the plane. When you are in instrument conditions and under ATC you can inform them of your possible sensitivity to the strobes.
If a passenger informs you of prior problems with flashing lights it is your responsibility to inform them of the dangers and decide how you intend to fly safely.
You can check with the Epilepsy Foundation Board for their strobe light recommendations. Two important things you can investigate are:
The photosensitive epilepsy becomes less frequent with age and usually disappears in the twenties. People without epilepsy are disturbed by light exposure do not develop seizures but experience other symptoms like headaches,nausea, dizziness and other debilitating effects.
People who experience seizures are unaware they are sensitive to flickering lights or to certain kinds of patterns. These people may never go on to develop epilepsy, which is characterized by recurrent spontaneous seizures, though a seizure may be triggered by certain photo-light conditions.
Television screen flickering, computer monitors that flicker, certain video games and TV broadcasts that contain rapid flashes or alternating patterns of different colors and intense strobe lights that may cause seizures in photosensitive people.
If you are photosensitive and you want to avoid the effects brought on by strobe light exposure you can cover one eye and turn away from the light source. This is difficult in a plane. A much easier solution is turning off the strobe light system for the plane. When you are in instrument conditions and under ATC you can inform them of your possible sensitivity to the strobes.
This is a safety item I use when fishing in isolated places. It is used to signal search and rescue folks.
If a passenger informs you of prior problems with flashing lights it is your responsibility to inform them of the dangers and decide how you intend to fly safely.
You can check with the Epilepsy Foundation Board for their strobe light recommendations. Two important things you can investigate are:
- Keep the flash under 2 Hertz with breaks every so often between flashes.
- Place flashing strobes at a distance from each other and set them to flash together to avoid an increase in the number of individual flashes.
I experienced one episode, with a passenger in the seat behind me, in a private plane on an instrument flight in a Beech-craft Bonanza. The plane was equipped with simultaneously firing wing-tip strobes and a fuselage strobe on the top of the aircraft that fired, by itself, after the wing-tip strobes. The plane was in heavy clouds with no turbulence and night was rapidly approaching.
The passenger became very agitated and began hitting me, from behind, with her purse. Luckily, her husband, sitting next to me, corrected her behavior and let me turn off the strobes. Things returned to normal and she apologized.
Another factor was claustrophobia. This was her first instrument flight in a small plane and the exposure to all the elements was overwhelming to her.
