Yeah, oven bulbs are 40w but make sure you don't get one that is 130v, otherwise subtract 25% from the lumens.
Measuring LED flicker - correlation with health symptoms
ryans Are the Phillips model 9290002268 still the best LED for you?
Maybe…I only have them in one ceiling fixture, though, and I don’t want to move them because their housing has cracked, so I haven’t been able to test them for constant use. Their flicker pattern is very different than any of the other low flicker LEDs that hurt me, and I’ve never been noticeably hurt the least bit by them in 10 years of daily use, so as far as I can tell, they’re good. I’m still using new-ish Waveform bulbs some time of the time and they seem ok, but I’m periodically checking their flicker with a meter. I’m still experimenting to try to figure out what’s the least harmful AC bulb option for me, whether incandescent or something else - and using sunlight, candles, or constant DC LEDs whenever possible since none of those hurt me and sunlight and candlelight seem to possibly help.
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jen Thanks @jen. I hope you can find a suitable bulb soon. I wonder if someone with knowledge of electrical engineering could design a "DC Lamp" that only provided direct current to any bulb? Then, flicker would no longer become a problem?
There are some new migraine medications (like Ajovy) I wonder if they can help us.
5 months later
Hi everyone,
Please check out my data correlating light and screen flicker with my concussion-like health symptoms posted here: https://www.flickersense.org/testing-leds-and-screens
I bought a professional UPRTek meter and have tested hundreds of light bulbs (dozens of kinds at least). I used this meter on screens too, but ended up also using microscopes and slow-motion video to quantify screen flicker better in 2 dimensions.
My basic conclusions are that for me, flicker is bad, color-to-color-flicker is much worse, and with limited data, there's a hint that randomness in flicker might reduce harm from flicker.
It turns out that the "good" Phillips LEDs I've used without harm since 2013 have 1% flicker, no color-to-color flicker, and happen to be in a fixture with a slightly unstable electrical supply that adds a little randomness to the flicker. So it's possible it's that randomness, rather than the bulbs themselves that makes them OK for me. Except for these Philips bulbs, I'm back to using incandescents at home.
All the screens I tested have significant flicker, especially at the subpixel level. It turns out that all of my screens flicker the red, green, and blue subpixels in order to decrease color saturation - so the amount of flicker varies for different colors. This happens at 15 Hz, 30 Hz, or 60 Hz depending on the screen. The 15 Hz LCD screen seems much more harmful to me than 30 Hz LCD screens. It's worse for me when there's more subpixel flicker and especially bad when the red, blue, and green flicker don't track with each other, creating color-to-color flicker.
Every screen I tested does something different with flicker, so it doesn't surprise me at all that sometimes those of us on this forum experience different things with different screens and it's hard to figure out general trends. Although one trend is that on all of my Apple devices, Nightshift works by adding somewhat more green and a lot more blue subpixel flicker, thus reducing the green-blue light. Now I know why my brain gets especially injured by Nightshift!...Why does Apple do this??
7 months later
The Illuminating Engineering Society (IES) has a new draft proposal for recommendations on LED light flicker (TLM) limits - a proposed update to the 2015 IEEE 1789 and other similar recommendations for limits on flicker in architectural lighting. It's currently open for public review though August 12, 2024. I just submitted several dozen comments proposing revisions. Participating in the review process means that I agreed not to distribute the proposal in its draft form (so can't share its details), but here's the process if any of you would like to comment too. They charge $25 - I asked if there was any way for people injured by LEDs to participate in the review without paying the fee (since it seems wrong to me), but got no reply on that.
So in case you'd like to participate too, what I had to do was:
- Go to https://www.ies.org/standards/ansi-standards-information/ and email the people listed toward the end of the page to ask to participate in the review of this Technical Memorandum:
"ANSI Standards: Open for public review
The following draft is available for ANSI Public Review comment Jun 28 – Aug 12, 2024:
BSR/IES TM-39 Technical Memorandum: Quantification and Specification of FlickerThis Technical Memorandum (TM) catalogs currently documented metrics and specification criteria related to the human perception of TLM, summarizes existing research, and identifies a path toward an IES standard method for quantifying and specifying flicker for architectural lighting. It excludes information regarding the effect of flicker on plants and animals. It also excludes information related to the measurement of TLM, which is covered in ANSI/IES LM-90-20."
They will reply with another link for you to purchase a copy for $25 and a description of the terms of participation. At that point I got stuck and had to contact them again to figure out that I had to create an account first before I could checkout using this link: https://idp.ies.org/Account/Login
After paying, they'll send another email with the document for review, a form for recording comments, and more submission directions.
I attempted to represent not only my own experience and data collection, but also what I've learned from others on the forum and others who I know in real life who are also experiencing health effects from LEDs.
Your mentioning of the 15 Hz frequency reminds me of flicker vertigo and strobe lights but in our situation it is rgb subpixels:
https://en.wikipedia.org/wiki/Flicker_vertigo
Flicker vertigo, sometimes called the Bucha effect, is "an imbalance in brain-cell activity caused by exposure to low-frequency flickering (or flashing) of a relatively bright light."[1] It is a disorientation-, vertigo-, and nausea-inducing effect of a strobe light flashing at 1 Hz to 20 Hz, approximately the frequency of human brainwaves.[2][3] The effects are similar to seizures caused by epilepsy (in particular photosensitive epilepsy), but are not restricted to people with histories of epilepsy.
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photon78s Yes, I agree - I think it's likely that flickering the screen subpixels at frequencies that are known to trigger severe neurological issues with architectural lighting could be a significant reason why many of us are harmed by screens. The subpixels can be large enough to be just barely individually visible, especially within something narrow, like a line in a text character. Even without obvious temporal dithering effects, the subpixel flicker seems to be bad for me, but the newer devices that are very likely to be adding temporal dithering seem to be even worse. Whether someone's symptoms are more similar to dry eye/eyestrain or migraine or concussion, or some mixture of those, all of the symptoms can have neurological causes, perhaps with some kind of light-triggered inflammation being part of the story too.
The research literature on digital eye strain/ computer vision syndrome has grown significantly since Covid, with clear links between more screen use and more symptoms in adults and children. The meta-analyses of survey data estimate the overall prevalence to be ~65% of people with suggestions of less screen time and more breaks being the only really helpful interventions (with little to no evidence for blue-blocking lenses being helpful). However, the optometrists and ophthalmologists are still only talking about eyes being tired/fatigued as the cause. They haven't started to really consider the issue of screen flicker. I suspect that part of the problem is that it isn't something they can fix with lenses or easily measure or change, so even if they think of it, it would be hard for them to study. I certainly don't believe that my eyes can get so tired within seconds that pressure builds in my temple and other concussion-like symptoms start. It seems that many of us similarly can have symptoms start within seconds, so I don't understand at all how "fatigue" could be the main problem. Years ago when I would just start to get minor headaches after hours on a computer, I might have been more receptive to the "fatigue" hypothesis, but not now. We need real research so badly...
This link is about a "low emissions computer" project relating to EMF sensitivity not specifically LED flicker. They use incandescent light for the display and a rear projection system. What I find also interesting is that it was funded by US Department of Education and the National Institute on Disability, Independent Living, and Rehabilitation Research.
9 months later
The Waveform A21 4006.27 100W equivalent is rated at 13.7 years at 3 hours a day on the package. That's 15,001.5 hours. (Website claims 25,000 hours in conflict with packaging. 25,000 hours over 13.7 years would be 5 hours a day.) There are 8,760 hours in one year burning the lamp 24/7. Note it has a 3 year warranty.
By hours alone a 24/7 operation lamp is better suited to the T8 tube lamps they offer. 50,000 hours and a 5 year warranty. They recently came out with the 3000K color option. This is equivalent in hours to T8 Fluorescent although turning fluorescent on/off say with motion sensing, or rooms visited frequently for short times like a laundry room, using instant start ballasts can severely reduce their hours. Short lamp life with frequent on/off in some rooms is one reason I wanted to move to LED.
I used the Waveform 4000K T8's, the A19 60W, and the A21 100W when I relamped my home. I did so partially on recommendations here, including yours, of flicker/strobe free. The cost was 2X replacing existing T8 tubes and electronic ballasts that had aged out (10 years old) to the point of strobing when filmed in slow motion. I kept only 3 LED A19 lamps I had installed over the years out of a mixed box of em as the rest also failed the slow motion video strobe test. The worst strobes were LED can light replacement's. Sadly some were the expensive single pack LED's with large finned heatsinks. Additionally a few had already shown the other LIE of long life by failing in less than 1-2 years. None were used 24/7.
The Waveform Lighting relamp project was successful in eliminating migraines for me and visiting family.
Some who are sensitive in my family do not like Waveform Lighting tube lamps seeing a flicker on the 4th lamp in a 4 light fixture. The T5 LED Linear Light Fixture under in cabinet use really bothers them with a flicker they can see. The A19 and A21's from Waveform do not bother them. Although it doesn't bother me the 1700K lamp was an instant "problem" to family and had to be shut off in seconds.
Who decided it was acceptable LED's could fail by blinking on/off? Some literally become a horror movie strobe light!
Waveform Lighting was easy to get warranty on a 100W equivalent A21 LED that failed by blinking when turning on along with a crackling of a bad connection or short. This left me with a failed LED lamp to autopsy.
Although there are several connections "pressed" together that could be the source of my problem the most likely outstanding component related to your flicker/strobe failure, Jen, is their use of Electrolytic Capacitors losing their capacitance. The hotter they get the shorter their life and they are life limited at specific temperatures. Their hours at a specific temperature are published and known. The bad formula capacitor plague of the 2000's affecting PC's, TV,s electronic florescent ballasts reminded us that solid state reliability is kneecapped by Electrolytic Capacitors. There are other types of longer life capacitors out there that do not use a liquid and have a higher heat rating for more lifetime hours. I can only guess as to if they got a bad batch or something else is causing the electronics to run hotter than designed.
I would pay more for a WaveForm Lighting lamp that uses something better than the life and heat limited Electrolytic Capacitors. It's bad enough that 99 cents would get you a 4 pack of incandescent bulbs … I will never recover the cost of these ~$30 each lamps in electric bill savings.
The failed A21 lamp used in a floor lamp base down, the most ideal cooling situation for the electronics in the base, had the heat shrink label on the Electrolytic Capacitors cracked and split possibly from being too hot in operation.
My thanks for the WARNING that LED's can also fail just like fluorescent with strobe and flicker. Sadly technology hasn't advanced...
Did you get any indication from Waveform Lighting as to if this was a bad production run or other reasons they had a short life before flickering/strobing?