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Use of strobes as risk to audience?

Discussion in 'Lighting and Electrics' started by jneveaux, Jun 4, 2009.

  1. jneveaux

    jneveaux Member

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    Just wondering if any of you have dealt with an issue raised by my director when I suggested use of strobe (flashing) lights as a transitional device for a scene that is supposed to depict a rapid and unrealistic series of events. She said, "Are you nuts? We can't do that! There might be epileptics in the audience and we'd cause them to have a seizure."
    I recognize that there is such a thing as "photosensitive epilepsy". See Epilepsy Foundation-Photosensitivity and Seizures. However, I have used strobes occasionally in other shows and have seen them used many more times for theatre and music productions. (I never had, nor am I aware that any of the other strobe users caused any adverse reactions in the audience.) Were they all "nuts"?
    Have any of you considered this as a concern and if so, how did you deal with it? If you didn't find it to be a prohibition on strobe use, did you take any other steps to warn of or limit exposure?
    Thanks in advance for your comments.
     
  2. David Ashton

    David Ashton Active Member

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    After 40 years of using strobes in discos and theatre with zero incidents I feel the "risk" is neglible, however in the interests of your clients a clear warning sign is a sensible initiative.
     
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  3. soundlight

    soundlight Well-Known Member

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    Warning signs should be placed at the door that say "Strobe lights will be used during tonight's performance" or something along those lines. Same thing for haze, same thing for cigarette smoke (even from those fake herbal cigarettes), same thing for pyro. I see these signs at most concerts that I go to, as well as most theatre and dance productions that use these effects.

    Anyone who is affected by them will still be able to sue the living *&$% out of you if they want to, because we Americans think we can sue for anything that's entirely our fault (seriously, people, grow up, you aren't entitled to damages for your own mishaps).
     
  4. Esoteric

    Esoteric Well-Known Member

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    You MUST post warning signs.

    But, the chances you will hit the exact frequency that sets off a seizure are little to none. In addition from what I understand to set off one, the effect has to either be an actual strobe or the light must be pointed directly at the person (for example a very rapid S4 chase would not do it).

    Mike
     
  5. headcrab

    headcrab Active Member

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    I heard that one "seizure frequency" is 4.5Hz.
     
  6. Sony

    Sony Active Member

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    Warning Signs must be posted! If an epileptic walks into your show with the warning signs posted then they are taking their own risks, THEY CANNOT SUE YOU. You gave them fair and proper warning and they decided to disregard the warning and risk their own safety. Most epileptics are aware that a lot of productions have strobes and they choose not to go since no one WANTS to have a seizure.

    At all of the theatres that I work at there are placards posted at the entrance of the theatre warning about smoke and strobe effects. It says something like this "Sensitivity Warning: smoke and strobe effects are used in this production." It's written in plain white on black Block Text in plain english so there is NO argument that they couldn't read it because it was in some weird font or some horrible color scheme.

    You should have no issues as long as you post warnings.
     
  7. epimetheus

    epimetheus Well-Known Member

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    As others had said, warning signs are a must. Clear phrasing with block text. "Strobe lights and atmospheric effects will be used during tonight's performance." I think that was the phrasing last time I saw such signs.
     
  8. Van

    Van CBMod CB Mods Premium Member

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    As the other have stated, warning signs must be posted. The same hold true for Pryo, Gunshots, Smoking, Haze, Fog, etc.

    The typical frequency for a strobe induced seizure is 8 flashes per second or aproximately 8Hz or faster these are the frecquencies at which brainwaves are actually modulating < though I believe Theta waves start at around 12 - 14 Hz but they are not the seizure freqs>. Not as well known is the fact that certain epileptics can have seizures induced by extremely loud noises, or extremely fast visual stimulus such as ...... Hmmm I'm thinking the way the Movie "Natural Born Killers" was shot with lots of camera movement, pans, cuts, close-up, back -off that sort of thing.
     
  9. gafftapegreenia

    gafftapegreenia CBMod CB Mods

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    As has been said, you MUST post warning signs.

    Make them look professional!
    SIGN BUILDER 2.0 - INDUSTRIAL SIGNAGE


    Derek, is this an appropriate use of the Warning header, or is Notice more appropriate?
     

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  10. theatre4jc

    theatre4jc Active Member

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    When I was in college our theatre would not only post signs out front but also included a tag onto the fire announcement in the pre-show.
     
  11. NickJones

    NickJones Active Member

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    Yes, some venues play "Welcome to (Insert venue name here) patrons please be advised that this show will include strobe & pyrotechnic effects"
     
  12. JD

    JD Well-Known Member

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    Signs and announcements are nice, and advisable. In 30 years of lighting, I have never seen it happen but have heard that it does.
     
  13. kiwitechgirl

    kiwitechgirl Well-Known Member

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    Only a very small percentage of epileptics are actually photo sensitive anyway (5% IIRC), and they tend to be aware of it. I've had a couple of people ask me if I can tell them where the strobe happens in the show, and I've been able to say "it's after this actor says this line so listen out for it" and have never had a problem. As others have said, put up clear and obvious warning notices and you are OK.
     
  14. FatherMurphy

    FatherMurphy Active Member

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    I worked in college with a girl who was epileptic, but wasn't aware of the strobe effect. While working a run of "Christmas Carol", she finally mentioned that she was going home each night and having minor seizures. The strobe thing was explained to her, she was reassigned to be elsewhere during the strobing, and the seizures cleared up. It does happen.

    Also, strobe-type warning beacons on machinery are set to flash at slow rates for seizure reasons, as well as power conservation. This was a major discussion point for railroad and teamster union negotiations in the 1950's.
     
  15. jneveaux

    jneveaux Member

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    thanks to all for the quick responses and thoughtful comments.
     
  16. zac850

    zac850 Well-Known Member

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    Anyone can sue anyone else if they want to, they might even win if they get a sympathetic jury (odds are the theater/school would choose to settle out of court as it would be cheeper and a good way to avoid bad press).

    However, lots of shows have strobes and cover themselves with a program note and a clearly visible sign in the lobby. Occasionally it is also in the preshow announcement, not a bad idea just for the added 'safety precaution'.

    Way back in 8th grade I was in a talent show and the flashing lights apparently set a girl in the audience into an epileptic seizure. I was acting in the show, so I don't know the particulars, but it did happen. She came out of the seizure, and we went on with the show. It does (and can) happen.
     
  17. Raktor

    Raktor Active Member

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    God I hate them.
     
  18. wakkoroti

    wakkoroti Member

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    The frequency we are held to avoid is between 4hz - 24hz.
     
  19. JD

    JD Well-Known Member

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    Just "Disney" it up with the signs like everyone says. As for lawsuits, we all remember the woman who sued McDonalds because she spilled hot coffee on herself. (And won!) Anybody can and will sue for any reason, and sometimes they win. Until crazy judges stop such cases in their tracks, we are all at danger of getting sued even if we never get out of bed!

    What we have to try and balance is to take all "reasonable" precautions, and hope for the best.
     
  20. jneveaux

    jneveaux Member

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    I hope we take reasonable precautions to be as safe as we can and to act with due care for the sake of our audience and participants. If we reduce ourselves to doing things just so we won't "get sued" then we are doing it for cynical reasons. Remember, getting sued and being liable are not the same.
     

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