Effective energy levels for long wavelength light therapy have decreased from 40 mW/cm² to around 1 mW/cm² in the lab, with lower levels showing effects.

“So people started off at say 40 mwatts per cime squared and I looked at that I thought criy >> that's bright >> that's bright >> that's very bright >> big after effect. >> Yeah that's going to make someone wse >> it is. So then we got ourselves down to what we do in the lab now generally which is around eight which is very comfortable has the same effect. >> Mhm. >> But then we had someone in the lab do an experiment um and we had the flashlights that had batteries in them. She got a lovely effect and we found out the batteries have been run down and she was getting an effect close at 1 mill per cm squared.”