Before you get the "blues" with LED, read this.
A report has been published by the American Medical Association (AMA) regarding blue light in LED Street Lights. They have concluded that LEDs with high levels of short wavelength blue light can result in health issues. - You can find a link to the report in this International Dark Sky Association (IDA) post: http://darksky.org/ama-report-affirms-human-health-impacts-from-leds/. This is a huge win for the IDA, which has been campaigning for better quality lighting for streets and public spaces for many years now.
Now, I appreciate this may seem a little left of centre for a story from Mint, given we're all about residential lighting design, but I want to nip in the bud the extrapolations that will very likely be used around the place regarding LED and “Blue Light Danger" at home.
For the past few years, various suppliers have purported to have "Low Blue Light" LEDs "for your safety", or have drummed up scare campaigns around the safety of LED used in the home related to some ambiguous, un-researched "Blue Light" component. A couple of years ago, this story was so strong in the commercial lighting supply world that I was asked to provide a report about potential "Blue Light" issues for some Australian manufacturers. New technology always seems to inspire these sorts of "half-truths".
So, now that a report has been prepared, by a widely respected organisation, that concludes there are some negative impacts from specific Blue Light spectrum in LED luminaires, I want to draw your attention to a critical quote from the IDA article - which captures the AMA position quite succinctly-
considering adaptive controls that can dim or extinguish light at night, and limiting the correlated colour temperature (CCT) of outdoor lighting to 3000 Kelvin (K) or lower. Color temperature is a measure of the spectral content of light, and higher CCT values indicate a greater amount of blue light that a fixture emits.
So, we can see that the problem is not "all LEDs". It is a subset of the LEDs on the market - and specifically some which have been used for Street Lighting without appropriate design considerations. Unfortunately, if past is present, this will not stop marketeers from leaping onto the "Blue Light" bandwagon left, right and centre for consumer products.
The most comforting thing (aside from the fact it backs up my report from a few years ago - phew!), for those of us that live and work with light (i.e.: everyone) is that it's really very simple to avoid any complications with LED lighting.
1. Use proper lighting design method so you have the right light in the right location (read: be properly informed, or hire someone who is - i.e.: A Lighting Consultant)
2. Use good quality luminaires (light fittings), that are designed for their specific location and use
3. Choose a warm colour temperature
4. Use lighting control to reduce your exposure to light at night
Number four is especially interesting as control equipment becomes cheaper, more effective and easier to install and use. There are myriad reports available that inform us that too much light late at night affects our sleep patterns. With control, it's such a simple fix - you can even pre-set your lighting to dim down, or change temperature to an even warmer glow AND dim down as the day comes to a close. So you can still enjoy the benefits of electric light - more day in which to be active - without the impact on the quality of your sleep.
So there you have it - yes, some very specific use LEDs (and possibly some of the very cheap stuff out in the marketplace) can result in negative health impacts through too much exposure to short wave blue light at night.
Happily, the solution is simple - choose appropriate professional advice, choose quality, choose warm and choose control over your lighting so you can enjoy the benefits of technology, without losing any sleep.