Recommendations

Product recommendations (based on my health experience):

Flicker measurements were performed by me - see Testing LEDs and Screens .

For safe lighting:

Almost completely safe lighting:

Safe LED lights (AC power):

LED lights that are less dangerous than other LEDs:

Safe screens

Products for protection from LED light or screen flicker

For detecting flicker (from least sensitive to most sensitive):

What people can do:

Based on the survey data, and until rigorous scientific studies can be conducted to delineate safe parameters for light flicker, I advocate for the following:

For lighting manufacturers and lighting professionals:

I think "flicker" should mean "flicker." Especially because the public needs to understand, "flicker" should be used in the sense that it is used by the general public and in the sense that it was often used by the lighting industry prior to 2016. Otherwise, how can the average person receive comprehensible information from the lighting industry? The lighting industry's current insistence that certain flicker is "temporal light modulation" but isn't "flicker" if it's not obviously visible creates considerable confusion. For example, using their industry-specific jargon, lighting professionals can currently tell people that the lights "don't flicker" even if they do flicker, as long as their flicker (temporal light modulation) isn't visible to average normal observers. This is despite the fact that research has shown that people can have headaches and eye strain due to flicker whether or not they consciously see it (see Background: Health Effects, including Brundrett, 1974, discussed in Background: Health Effects of flicker below 100 Hz). 

The ability of lighting professionals to deny the existence of flicker through industry-specific language can increase the likelihood that third parties, like employers or medical professionals, might dismiss the health concerns of sensitive individuals. Sensitive individuals face an uphill battle convincing others that they are hurt by light that many people don't sense could be causing injury. They face medical professionals who might dismiss their condition as psychosomatic (see discussion of the "sunglasses sign" in Background: Unanswered questions), they face employers who might question their truthfulness or mental health, they face lighting consultants who have a monetary interest in not admitting that the lights they have specified are unhealthy, and they face lighting manufacturers that are not likely to appreciate reports that their products are unsafe. Sensitive individuals, who may be experiencing significant neurological symptoms, should not also be burdened with navigating unnecessarily confusing industry-specific language.

Pst and SVM are not useful metrics for protecting sensitive individuals from flicker ≥100 Hz that is produced by LED lights. Pst is only used for flicker <80 Hz. SVM is a measure of flicker visibility based on average normal observers and the current SVM limit proposed by the lighting industry is much more permissive of flicker than the previously-developed IEEE recommendations (see Background: LED lights). My personal experience is that the IEEE recommendations for flicker are not close to stringent enough (see Testing LEDs and Screens). None of these current metrics are based on any studies of the health effects of flicker ≥100 Hz.

For policy makers:

For scientists and engineers:

For medical professionals:

For health departments and health-related government agencies:

For businesses and the building design industry:

Edwards, L. & Torcellini, P. A Literature Review of the Effects of Natural Light on Building Occupants, National Renewable Energy Laboratory TP-550-30769, July 2002. https://www.nrel.gov/docs/fy02osti/30769.pdf

For the computer, television and video industries

For parents and educators:

For allies:

For people struggling with sensitivity to LED lights and/or screens: