Can flashing lights cause epileptic fits?

[Drago]

The HSE no longer allow flashing lights in 'Discos' beyond 4hz, so you won't fit. Similar rules govern TV and flashing stuff and OFCUM enforce that.

In my nieces case it's sunlight shining through trees and railings etc while travelling in the car that trigger hers. At first my bro in law fitted blinds to the car but now she had tablets that eliminate it entirely. The drugs to control this form of epilepsy are supposed to be superb, almost universally effective.

 

[machew]

She must have a rare form then, the following have set off a fit
Advertising hoardings for 888.com at the football ground
Flashing lights at a rock festival
And the best one, the blue lights on the ambo that came to pick her up (she had stopped fitting for about 10 mins before they came, put started again a few moments after they turned up)

 

[ColinJ]

The HSE no longer allow flashing lights in 'Discos' beyond 4hz, so you won't fit. Similar rules govern TV and flashing stuff and OFCUM enforce that.

In my nieces case it's sunlight shining through trees and railings etc while travelling in the car that trigger hers. At first my bro in law fitted blinds to the car but now she had tablets that eliminate it entirely. The drugs to control this form of epilepsy are supposed to be superb, almost universally effective.

I don't know what frequency my bike light flashes at but it is bang in the middle of the range which I find annoying. It is fast enough to be disturbing, but not fast enough to appear continuously on.

I used to feel bad when zapped by disco strobe lights, and I also suffer from the sunlight-through-trees/railings problem.

I don't have seizures, but I really don't like exposure to rapidly-flashing bright lights.

I am very sensitive to light levels and I suffer from SAD. On summer days with dark broken clouds blowing over it feels like someone is messing with my head - depressed-cheerful-depressed-cheerful ...

 

[Grizzly]

I've never known anyone to complain about the flashing lights on emergency vehicles and they are brighter and faster than bike lights.

 

[HLaB]

As an old epileptic I can safely say that If I went to a disco I would perhaps fit. But as most of the flashing lights on bikes are nowhere near as bright as in a Disco I can't myself say that it does affect me, but then perhaps I'm not as epileptic as some other people are as it is an affliction of different degrees.

I'm an old epileptic too and I stayed away for years from things like disco but tbh all it served to do was make me miss out on my teen/early 20's years and when I eventually went to one I wished I had earlier.

 

[TonyEnjoyD]

To trigger photo-sensitive epilepsy, there has to be a specific set of curcumstances, and flashing bike lights are variable dances and often in amongst other light sources and at varied angles.
Also, you can also check the flash frequency as it may already be deigned at a rate known not to cause PS epilepsy

"A flashing strobe (or a close combination of multiple strobes sequenced together) must not be programmed to flash in the 5 Hz to 70 Hz frequency range.
Slower flash rates, and randomly flashing lights are not known to be a cause of photosensitive epilepsy.
Point sources of light are much less likely to induce seizures than a diffuse source of light which covers a large part of a person's field of vision.
To induce a seizure the light must be present in the center of the field of vision as opposed to the periphery.
Reducing brightness or increasing distance between a photosensitive viewer and the light source is effective for preventing photosensitive epileptic seizures.
Lights flashing in the distance, even in the frequency range of concern, are not known to cause seizures when in the presence of other lights of a more natural or chaotic nature"

I'm keeping mine operational

 

[Rohloff_Brompton_Rider]

As I said in my op my maglite flashes brightly and very very quickly, eye catching for motorists.....not so healthy for epileptic people.

It is something I can change without a lot of effort, therefore I will.

 

[classic33]

Photosensitive epilepsy is massively bigged up, mainly thanks to a scene in The Andromeda Strain where a scientist has a fit because of a flashing red emergency light.

Only 3% of those with epilepsy have this form, and the majority of those are sensitive in the 16-25hz region, which is very fast. Flashing strip lights, tv's, bike lights etc are simply not capable of triggering such an episode. There is some variance outside this threshold but its very, very rare. What the British Epilieptic Association claim about bike lights is not backed up be any science. I know all this because my youngest niece suffers.

So now you know more than the very people researching the condition! Research that has been done freee over many years, by many people.
We are free to say what we want, within reason.

IF the condition is "massively bigged up" it isn't due soley to a scene from one movie from 1971. Its only within the last 10 years that the warnings have been given about flash photography/flashing images. I don't know why, but it annoys the hell out of me when its used as a reason for not allowing me to do something.
I worked in an office enviroment where if I sat still for longer than a few seconds, someone would be sent to check on me to see if I was ok.

Ignorance it seems is king in situations like this. I use flashing lights, front & rear & I've followed vehicles with flashing lights with no ill effects. Think about indicators on motor vehicles, how often is a person going to come across those. I know their use is falling out of favour, but some people still use them.

 

[machew]

"Dennō Senshi Porygon" was a cartoon that caused seizures in 685 viewers that required a hospital visit. And about 12,000 viewers had a seizure type episode. This was from a clip that had strobes in about 12 Hz for about four to six seconds (wiki link)

 

[Nebulous]

A lot of very categoric statements here. While much of it could well be applicable to individuals, or small groups of people, it certainly isn't to everyone. Epilepsy can be very individual.

Just to pick up on some things. TVs certainly cause a problem for some people, as can computer screens and fluorescent lights for that matter. With computers bumping up the refresh rate can help and modern graphics cards are usually ok with that. Older ones weren't. There's some variation in TVs now with fancy ones often being at 100hz or even 200hz but older ones were all at 50. If people do have a problem then as was said earlier how much of your field of vision it fills is important so placing chairs at the opposite side of the room may help, as could having a smaller TV. When you come into DVDs/ bluray players it all changes again. My bluray player is at a cinema standard 24 hertz while dvds were almost all at 25. So it's quite feasible that some people could watch TV but not DVD/ blurays.

The problem with the unusual or different, like a strange random flash mode, is that people often don't know it is a problem for them until it strikes. With flashing lights it maybe a first seizure, so people could well be driving for instance when they are affected.

My Cateye back-up flash is quite a slow flash and I use my main light on solid. I think its very unlikely my cateye would affect anyone. My rear light on my roadbike has two flash modes and I generally put it on the slow one. It's also not very high powered. I'd be very wary about using a high powered led on a quick flash.

 

[siadwell]

If you read the descriptions of some of these cheap torches used as bike lights, the flashing mode is described as a fast strobe mode and is designed to disorientate an attacker. The crenelated bezel on some of these torches is also described as an "assault crown", leaving you in no doubt as to their defensive intentions. Basically, I wouldn't use such a fast flash on the road, no matter how eye-catching.

 

[Globalti]

I'm going to wear flashing lights when I go skiing next week and I think every other skier ought to as well.

 

[sabian92]

It CAN trigger fits but most epileptics aren't light sensitive, contrary to popular belief. Most are stress induced, and lights don't bother them. My dad is an epileptic and can drive, watch TV, use a PC and everything in between and has only had a fit when stressed, and the last one was over 4 years ago.

 

[snailracer]

The British Standard for bike lights specifies that their flash rate shall be between 1 and 4 times per second.

 

[Night Train]

There are plenty of LED lights on the backs of pricey German cars and even in traffic lights, and although they flash much, much faster (to the point that they appear to be solid) and are much brighter than (most) bike lights I don't read too many complaints about those.

Those lights make me nauseous. They are fine if I am looking straight at them but, when driving, I am scanning the roads and the lights leave tracking dots of lights across my vision. I don't like them at all.