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  • Fluorescent lites

    I had a real bad headache all day Saturday. In this mornings paper an article stating one major cause of headaches is fluorescent lighting......DAM just installed 4 -4tube lites in my shop about 3 months ago. Been replacing incandescents in the house with those cf's.....Just can't win...
    Gary Davison
    Tarkio, Mo.

  • #2
    The 6500K spectrum bulbs may be closer to natural light. You might give them a try.

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    • #3
      You might also try switching to electronic ballasts as they don't flicker like the conventional ballasts do. That may be a significant factor.
      Home, down in the valley behind the Red Angus
      Bad Decisions Make Good Stories​

      Location: British Columbia

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      • #4
        Originally posted by Willy
        You might also try switching to electronic ballasts as they don't flicker like the conventional ballasts do. That may be a significant factor.

        If this becomes an everyday occurrence I'll try that.
        Thanks Willy
        Gary Davison
        Tarkio, Mo.

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        • #5
          regular flourescent tubes absolutly give me a headache if working under them long enough, the cf jobs don't seem to bother me at all.
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          • #6
            STRONGLY doubt it is the flicker, which is actually minimal, due to the phosphor coating smoothing it out.

            The MAIN problem with fluorescent lights is the "cool white" bulbs that are cheap and used everywhere.

            That light gives me a feeling that my eyes are being pulled out of my head. To counter-act it, I install at least one "warm white" or similar light in every fixture or array, and that seems to help quite a bit.

            "Warm white", "kitchen and bath", "daylight", almost any of those works. The idea is to get more "red" into the light. That frosty cold blue light from the "cool white" bulbs is bad.
            1601

            Keep eye on ball.
            Hashim Khan

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            • #7
              JT, that is what I feel like when I use cheap binoculars or rifle scopes.

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              • #8
                I think you will find that a lot of the newer Cf's are high frequency units that shouldn't give any flicker. The larger fluorescent that have a ballast choke definately flicker or strobe, I seem to remember in the past that they were not reckomende for rotating machinery because of the stobe effect on rotating objects. I think you can get high frequency units for larger tubes albeit at ahigher cost, aint it always the way of things!!
                Peter
                I have tools I don't know how to use!!

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                • #9
                  Originally posted by ptjw7uk
                  I think you will find that a lot of the newer Cf's are high frequency units that shouldn't give any flicker. The larger fluorescent that have a ballast choke definately flicker or strobe, I seem to remember in the past that they were not reckomende for rotating machinery because of the stobe effect on rotating objects.
                  They won't "freeze" a rotating object. There is always a persistent "green flash" that allows you to see the object as spinning.

                  Possibly old ones had a shorter duration phosphor.
                  1601

                  Keep eye on ball.
                  Hashim Khan

                  Comment


                  • #10
                    Headaches from fluorescent lights is well documented phenomena associated with the flicker found in fixtures without electronic ballasts. Compact fluorescents are not subject to this because they of course have an electronic ballast,( which may self-destruct!).

                    Color temperature also is a factor. Blending incandescents with fluorescents is a good way to ease the strain prevalent with that cold knock your eyes out cold blue light.

                    Some people obviously are more sensitive to the strobe effect from fluorescents than others, but the number that are effected is quite significant. I personally have no problem with it myself as I have new fluorescents with electronic ballasts in one shop and old style ones in the other and don't have a problem with either one, but I do have guests that are affected by the old ones. But that's a good thing cause then they'll leave.
                    Home, down in the valley behind the Red Angus
                    Bad Decisions Make Good Stories​

                    Location: British Columbia

                    Comment


                    • #11
                      I have a lot of dual 4 ft fixtures in my shop. In each one I installed one warm white and one 'day glo' tube. That's so much better than two cheap cool whites. I had the opportunity to compare the difference a year or so ago when one of the fixtures started weakening. I bought two cool whites 'cause they were cheap and I just wanted some light back in that area. Put the new tubes in, yuk I hate it.

                      I must have about 20 cfs now in various places. I like the warm white and the daylight, but I don't like the cools. Same deal. I thought I might find the cfs annoying, at least after some time, but that hasn't happened yet. The most annoying thing is that some are slow to start. Most take a few minutes to come to full brightness, but if they don't start up within two or three seconds at a reasonable brightness, they go back to the store.

                      I don't typically have single sockets where I replace an incandescent with a cf, except a couple hallway lights, so I do the same routine I did before with the tubes- make each pair one warm white and one daylight. I haven't had any ill feeling working for long periods under that combination.

                      Those hot halogens- not for me either. The larger shop type lights, sodium halide or whatever they are- I don't like them but I'm ok if I don't look at them. They are closer to daylight, but still work off a standard ballast, so there's the flicker factor that could be causing my dislike of them.
                      I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                      • #12
                        Originally posted by Willy
                        Headaches from fluorescent lights is well documented phenomena associated with the flicker found in fixtures without electronic ballasts. Compact fluorescents are not subject to this because they of course have an electronic ballast,( which may self-destruct!).
                        Astounding.............

                        "Swinging eye test" shows essentially ZERO flicker with all the flourescent fixtures I can find to check. This consists in swinging your gaze across the area without focusing.

                        With an LED-based light, it is usually possible to see a very plain "dotted line" of flashes. Most LED traffic lights do that, for instance.

                        I cannot detect it in the fluorescents here. I can see a slight shadowing on rotating cutters, so there is SOME change of intensity, but it is slight.

                        If it is hard to find when you WANT to find it, it may not be sufficiently large for a measurable effect.

                        It leads me to seriously question whether the "studies" have controlled for the proper things and found the real effect.

                        Did they contrast a "DC fluorescent" (obviously zero flicker but same light) with an "AC fluorescent"? Or did they just contrast fluorescents with another type of lamp?
                        1601

                        Keep eye on ball.
                        Hashim Khan

                        Comment


                        • #13
                          Originally posted by J Tiers
                          Astounding.............



                          Did they contrast a "DC fluorescent" (obviously zero flicker but same light) with an "AC fluorescent"? Or did they just contrast fluorescents with another type of lamp?

                          Not sure JT, but I sincerely doubt it, I'm sure a lot of these "studies" are knee-jerk to say the least. I certainly can't speak from first hand experience as it doesn't effect me in the least, but I do think the issue is real enough for some people. I really can't see a detrimental effect emanating from DC fluorescents because as you pointed out, there cannot be any flicker from a direct current source. But according to the "studies" a high frequency electronic ballast operating at 20-60 khz does not effect those that are susceptible to the 60 hz flicker.

                          As I said, it's a non issue with me so I don't even know what all the fuss is about. I'm just being the devil's advocate as it were.

                          Just do a search for "fluorescent flicker headaches" and I'm sure you'll find enough ammo to initiate a government grant!

                          Here's a few to get you started:

                          http://ergonomics.about.com/od/ergon...orproblems.htm


                          http://www.ccohs.ca/oshanswers/ergon...g_flicker.html

                          http://www.ehso.com/fluorescent_safety.php
                          Home, down in the valley behind the Red Angus
                          Bad Decisions Make Good Stories​

                          Location: British Columbia

                          Comment


                          • #14
                            When I was a teenager ( yes I can remember that far back) I played around with fluorescent tubes. The neatest one I had was brilliant green- but that's irrelevant. I had made a pulse circuit with a transformer and the output was voltage spikes, pulses with mostly dead times between. I fed it to a fluorescent tube and was able to make it flash. We took pictures at night of my friend running in front of the camera- got three or four sharp images in a row of him on one of the pictures. The phosphor was obviously responding fairly quickly to the pulses.

                            Running off a ballast I can see the 'on' time of a tube being longer than the off time, and I can also see some on time with weaker voltage and thus weaker light output. The tube may well be putting out a resonably even amount of light for most of each half-cycle, but it is dimming down a lot during the low voltage periods. If it wasn't for this, my strobe discs wouldn't be working at all. They do work, so that means that there are periods per cycle that vary in intensity, and it's well defined, if not sharp. I don't expect it to be sharp either, because phosphor has persistence, which means it will continue to glow for a time after all excitation has ceased. This glow is at a much lower level though, and light coming from the phosphor will decay to this level fairly quickly, fast enough that the 120 bright periods per second are interspersed with 120 darker periods per second.

                            Flicker does exist. In the case of fluorescent tubes, it's both light output-wise and electromagnetic-wise. You're standing under an electromagnet where the current flow is zapping on and off constantly. That's the buzz you hear on top of the hum. To what extent it affects people I can't say, except for myself. Sometimes I'm bothered by fluorescent lights, sometimes not. If I'm tired or ill, it's worse. It's not just the cool whites, my combo warm and dayglo does that to me sometimes as well. I have not had that with the cfs.

                            I think it's quite possible that a person's brain trains itself to subjectively even out those pulses of light (basically ignores it) because it can, and when you're ailing your 'powers' are lower and then maybe it bothers.

                            What's always been the case is that it's difficult to pin down an exact cause of a discomfort or actual illness much of the time. There are too many factors. To say that it's these standard fluorescents that are giving me a headache may be partially jumping to a conclusion, but to say that this phenomenon doesn't happen is also jumping to a conclusion without sufficient evidence. This type of evidence is very hard to gather, if not impossible.

                            I'm no miracle medical man of galactic repute, so take what I'm saying as just my experience mixed with some experimental data gathered without an air-tight study process, mixed with objectivity and some conjecture- even some rationality.

                            As far as Willys headaches, he'll have to pin down whether the lights in the shop are affecting him, or what other factors are also possibilities. There are so many bugs these days, so many ways of contracting them, so many people spreading them, etc- around here it seems there's never a time when there isn't something going around.

                            Do you like to go for coffee, maybe read the newspaper? There's a sure-fire way to pick up some bugs. I went to McDonalds tonite ( I know, HORK, RETCH, etc) - the girl who drew my drink had moments before taken my cash, plus cash from other people, then with the same hand put two fingers inside my cup while taking it to the coke machine. Ever see them at Tim Hortons take a bare hand (after handling cash and all the keys on the machine) and shove it into your bag to open it, then take a waxed paper to pick up your dognut and carefully drop it in the bag without touching it? Ever see a waitress carry somebody's finished plate away with a bare hand, then pick up your cup by the rim to top you up- how many opportunities can you find to pick up germs- doorknobs, tap handles, fridge handles (a good source right there) - it has been said that the steering wheel is a breeding ground for germs. Got kids in school- it's likely that in many cases, a headache is the only symptom that your body is fighting something. Headache goes away, great. You might not be thinking that a bug had invaded you, cause your body fought it off and then you feel ok again.

                            Sometimes I think wouldn't it be good if you could see all those potential germs in the air, good or bad- maybe color coded to distinguish them- but then I think, no way, there's be nowhere you could go, except nuts.

                            Other factors for headaches- I used to have headaches all the time as a teen and pre-teen. I learned to make them go away by envisioning my blood pressure going to my hands rather than my head. A couple months ago a friend told me, out of the blue, that he had been using that technique that I taught him decades ago, and that it still works for him. I don't often get that kind of headache anymore, but when I do it still works for me.
                            I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                            • #15
                              I also have to question the validity of the tests on this one. Often the people making such tests are not properly trained in the scientific method and they have a cause that they want to support.

                              If you are bothered by fluorescent lights and think it is the flicker, ask yourself if you have any problems with CRT television viewing. It has the same light producing mechanism, exciting phospors and it does it at the same frequency, twice the line frequency or 120 Hertz in the US. If you can view TV for hours with no ill effects, then I doubt that the flicker is bothering you.

                              I also doubt it is any electromagnetic field effect. We are totally bombarded with EM fields in this day and age and fluroescent lights are probably a VERY minor contributor.

                              I would first tend to suspect either the color temperature or the sonic emissions that cheap ballasts and/or tubes are prone to make. Many people are quite sensitive to high frequency sounds.

                              As for the DC thing, before you think there is a difference, check the regulation or filtering of the DC being used. It is common to call rectified but unfiltered AC, direct current. More correctly, it should be called pulsating DC. If it is not filtered then it will have the exact same effect on flicker as the original AC current would. In fact, every DC power supply that operates from the AC line has some AC component remaining in it's output. The better ones have less, but it is there. Check out the specs on several and you will see. Look for AC ripple or 60/120 Hertz component.
                              Last edited by Paul Alciatore; 02-04-2008, 03:34 AM.
                              Paul A.
                              SE Texas

                              Make it fit.
                              You can't win and there IS a penalty for trying!

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