Thanks, I am still working through all your excellent replys, and the links which you have kindly given.
Thanks to TwoFlower who gave the paper from Wilkins. This strategically avoided declaring any definite biological health risks of flicker......
https://www.ece.neu.edu/groups/power/lehman/Publications/Pub2010/2010_9_Wilkins.pdf.....It said that the worst flicker was 3-70hz, and that this can sometimes occur in leds or fluo’s that have undergone some kind of failure giving unbalanced driving of the lamp.
Also, Derlichtpeter,
https://www.derlichtpeter.de/en/light-flicker/cfd/….kindly given by Maukka, tells us that DIN EN 12464 actually bans high levels of 100Hz flicker for indoor , or outdoor work related use. It says that it is “hazardous for work and must be avoided”….but there was no mention of any law against using these kind of lamps. Surely if it was really dangerous then there would be a law against it?
Also, surely if 100Hz flicker is that bad, then the safety standard that pertains to it (EN 12464) would be free-of-charge…I mean, it would be inhumane to charge money for something that was needed for peoples safety….but perhaps 100hz flicker isn’t really dangerous after all?..so that’s maybe why they charge money for EN12464… I would certainly like to see the section where it declares that 100Hz flicker at CFD >75% is hazardous and to be avoided. What is the penalty for seeling such products?…there was no mention of this…and surely there would be if it really was hazardous?
I am afraid I just can’t believe it……there are loads of retrofit led light bulbs in the supermarkets that are compatible with phase cut dimmers……..and these produce really high levels of 100hz flicker…and yet these products do not have safety warnings on them…and are sold by the millions and millions.
If we are saying that 100Hz flicker is dangerous and hazardous…..then it would be illegal to illuminate roads with 100hz flickering streetlights…and this is not the case…loads of roads are illuminated thus, and there are no overly large incidences of accidents on such stretches of roads.
Again, there would be defined laws against deep 100hz flicker if it really was as hazardous as declared. There would be stories of people going to prison for flogging deeply 100hz flickering lighting….these stories do not exist.
What I can see, is that there is a definite motive for spreading stories that 100hz flicker is hazardous…that is, the large electronics corporations have set out their stall to sell flicker-free led lighting drivers in huge quantities…these comprise significant electrolytic capacitor banks which make it easy to do away with 100hz flicker…….and so what they then do, to kill off smaller companies trying to sell 100hz flickering lights, is spread stories that 100hz flicker is dangerous and hazardous.
I still fail to find actual laws banning 100hz flicker. There would be actual laws if it really was hazardous. If EN12464 really says that 100hz flicker should be avoided due to health reasons, then surely EN12464 would be freely available, for reasons of humanity?