TM-39-25 Erratum
TM-39-25 includes anecdotes from a few people adversely affected by flicker, which is a wonderful addition in that the voices of those being injured are starting to be platformed. One of these anecdotes is mine and through unfortunate accidents, an unapproved draft version that was a mixture of my initially-submitted statement from the summer of 2023 and additions and other edits made by another person that included 3 false statements was not replaced with a corrected version prior to publication and is now being corrected with an erratum. Even though the error happened, I am still thrilled that people injured by LED lights are beginning to be heard by lighting specialists.
The 3 false statements in the originally published version are:
The false statement that fluorescent lights do not injure me. They do injure me, just less than most LED lights. I didn't notice harm from fluorescent lights prior to 2018, but in retrospect, it's likely that they contributed along with screen use to occasional headaches. Following LED injury in 2018, fluorescent lights became a little painful. Pain subsided as LED injury symptoms subsided, but pain returned following other serious LED injuries. Also after 2018, extended fluorescent light exposure hurt and seemed to exacerbate LED injury symptoms, especially in locations and at times when there was low sunlight. I think this was important to correct because all clues about the differences between safe and unsafe lights for injured people are important during this time that the question of what kind of flicker is safe is under investigation.
The false statement that it takes at least minutes for my LED symptoms to start. The truth is that some symptoms can start within seconds or immediately. I think this was important to correct because the argument is sometimes made that fatigue causes symptoms, but that doesn't fit with the fairly immediate symptom onset experienced by me and others.
The implication that I consider myself to always be disabled. The truth is that I feel fairly normal as long as I avoid LED lights and screens, assuming I've recovered enough from prior injuries for debilitating symptoms to have gone away.
The corrected version of my anecdote submitted in the summer of 2024 that was supposed to have been published is below.
“In retrospect, more frequent headaches during electronic display screen use and a new inability to concentrate on grading students' work at night under LED light were probably misunderstood early warning signs that screens or LED lights might harm my health. However, a 2018 workplace shift to LED lights with "invisible" flicker made it obvious: a shockingly intense, sharp pain in my head present only every time I was in the LED light preceded persistent concussion-like symptoms that include head pressure with dull pain behind an eye, nausea, a feeling of low brain blood pressure or brain fog, reduced sensing of gravity with impaired balance, insomnia, occasional migraine, and such profound short-term memory impairment that I could no longer add a series of single-digit numbers. While weeks away from screens and LED lights largely restored my health, increased sensitivity remained. Debilitating symptoms quickly return with exposure to typical LED lights with flicker invisible to me, often within seconds, and symptoms can last for weeks to months after only minutes to hours of exposure. Over time, symptoms have tended to have greater intensity, start faster, last longer, and be triggered by a wider range of devices with flicker. More symptoms have appeared, including peripheral blindness, occasional blurriness and other visual anomalies, allodynia, and especially severe brain fog. My health seems unaffected by sunlight, candlelight, incandescent lights that produce less than ~6% flicker, or rare LEDs with no or exceptionally low flicker. No medical basis for my symptoms has been found and so far, no lens filter or medication has helped. Due to the near-ubiquity of LED and screen flicker, serious long-term disability has become the cost for me of most access to food, healthcare, education, travel, social gatherings, cultural events, and the workplace. To retain brain health, I almost always have to avoid these since I haven't yet found any screens or commercial LED lights that are safe for me.”
A different, truncated version ot the statement that only corrects false statements in the published version was agreed to for the erratum so that (1) re-typesetting the rest of the document wouldn't be required and (2) to clearly show which originally-published parts were false, given the inability to include an explanation with the erratum. The erratum retains edited portions not originally written by me as long as they are not false.
Illuminating Engineering Society. ANSI/IES TM-39-25, Technical Memorandum: Quantification and Specification of Visual Responses to Temporal Light Modulation (a.k.a. Flicker). New York: IES; 2025. https://store.ies.org/product/technical-memorandum-quantification-and-specification-of-visual-responses-to-temporal-light-modulation-a-k-a-flicker/?v=0b3b97fa6688