some cities are taking another look at led lighting after ama warning
On June, the American Medical Association issued a warning saying that,
LED street light-strength
Seattle, Los Angeles, New York, Houston, and other places.
Sending out an invisible blue light can disrupt the rhythm of sleep and can increase the risk of serious health conditions such as cancer and cardiovascular disease.
AMA also warned that the lightemitting-
The diode light will damage the vision of driving at night.
Similar concerns have been raised over the past few years, but the AMA report adds credibility to the issue and may prompt cities and states to reassess the strength of the LED lights they have installed.
According to a report prepared for DOE last year, nearly 13% of the area and road lighting are now LED, as are many communities that have not yet made a switch plan.
Led energy increased by 50%
More efficient than yelloworange high-
They usually change pressure sodium lamps.
They lasted 15 to 20 years instead of 2 to 5 years.
Unlike sodium lamps, LEDs are illuminated evenly.
Some cities say health concerns are not enough to be convincing enough to go beyond the first
They have installed a generation of bright LED lights in the last three to eight years.
New York is one of them, although it has responded to complaints from residents by replacing the top
White LED bulbs with lower strength
The intensity bulb that AMA considers safe.
Seattle city lighting spokesman Scott Thomson, who is in charge of lighting outside the city of Seattle, denied concerns about bright health.
White LED lights, pointing out that they issue fewer blue wavelengths than most computers and televisions.
After a year and a half of discussion and sampling, Lake Worth, Florida.
, Is replacing sodium street lamps with about 4,150 LED lights with Amber gloss.
\"We have found a color that makes sense to the health of our city and we are proud of the choices we make,\" said City Manager Michael boenstein . \".
Mark Hartman, chief sustainability officer in Phoenix, said the city may use a mix of bright lights at major intersections and baseball field areas that require very bright light and soft light in residential areas.
He said that although he also mentioned the light of computers and television, the city will consider health issues.
\"No one said not to watch TV or use the computer after 9. m.
Because of the blue lights, \"he said.
Almost as soon as there are outdoor LEDs, the federal government encourages states and municipalities to use them, saying LEDs are very effective in applications such as traffic lights and exit signs.
But critics say the federal government is too fast to support the led.
Michael Siminovitch, director of the California Lighting Technology Center at the University of California, Davis, said the Department of Energy and the Environmental Protection Agency \"put a lot of effort \".
\"I call it a rush.
Siminovitch says early light
\"It has had a negative impact on people\'s physical health --being.
The lighting is measured with a color temperature, which is represented by \"Kelvin\" or \"K.
\"The temperature of the original LED street light was at least 4000 K, which produced a bright white light with invisible blue light.
Now, the Kelvin rating of the led is lower, and the energy efficiency is roughly the same as that of the led with higher ratings.
There are not many potentially harmful blue light they emit, and they produce a soft amber hue.
When 4000 K and 5000 K LEDs are installed, they cause a mixed response.
Police and traffic
Security officials and many motorists like them because they create bright light that makes the ground they cover bright.
But in many places, including New York and Seattle, residents complain that bright white light is dazzling and even terrible.
People describe them as aggressive, cold and unlikable.
Even before the AMA warning, some researchers raised health issues.
Some pointed out that exposure to blue
Rich LED outdoor lighting may reduce the secretion of melatonin in the human body.
Melatonin is secreted at night, helping to balance reproduction, thyroid and adrenaline, and regulate the circadian rhythm of sleep and waking in the body.
\"As a species, we are not designed to see light at night,\" Siminovitch said . \".
At the same time, the \"dark sky\" campaign criticized LEDs as a major contributor to the \"light pollution\" that humans enter the night sky.
AMA cited the melatonin problem in the warning, noting that studies have shown that bright led is associated with shorter sleep time, poor sleep quality, and impaired daytime function.
It mentions exposure to high-
Bright light at night may increase the risk of cancer, diabetes, cardiovascular disease and obesity.
It warns that strong LEDs are associated with \"discomfort and disability glare\", which can damage the driver\'s night vision.
Finally, AMA warns against the harmful effects of bright led on wildlife, especially night animals, birds and insects.
Mario Motta, one of the authors of the AMA report, said: \"These lights are not only harmful to us, but also to the environment.
AMA does praise the energy efficiency and effectiveness of the led, but it urges the city to be blue-
Rich external lighting, it is recommended to use LEDs that do not exceed 3000 K.
Tony Dorsey, spokesman for the National Association of Road and transport officials, said the organization\'s environmental committee was studying the AMA report, but members of the Association seem to be concerned about the use of 4000 LEDs on the road.
The Department of Energy said the led should be used \"cautiously\" but praised its overall performance.
It said AMA added \"another influential voice\" to the issue \".
Others, including the Lighting Research Center at rensler Institute of Technology in Troy, New YorkY.
Lighting is less risky than AMA suggested, he said.
The Research Center noted that the AMA report is based on long-term exposure to high
Representation of intensity LEDs and blue
In most lighting applications, the light hazard of the led \"may not be a concern for most people.
Morta supports AMA to Gao-
The intensity LEDs and indicate that there are no shortcomings
Both cost and efficiency
Choose a lower oneIntensity light.
Some cities are high on them.
The strength of LED street lamps.
About 41,000 new lights have been installed in Seattle since 2010. Attribute early complaints to residents\' surprise at the difference in brightness between old sodium lamps and new LEDs.
Thomson said the light of the new light fixture is comparable to the Moonlight, providing the driver with excellent vision.
Police especially like them, he said, because they can make people distinguish colors at night.
\"The police said they got better witness descriptions,\" Thomson said . \".
Thomson also noted that although the Seattle led is rated at 4100 K, it is much lower than most computer screens, laptops and televisions.
But Pete Struthers, technical director of the International Dark organization
The Sky Association says the Moonlight is much less than the blue light in the high area.
LED light for strength.
Gloucester, Mass more than a year ago.
, Is replacing its sodium street lamp with a 4000 K LEDs.
But city planner Matt Coogan started reading about health and environmental warnings.
He also asked residents to sample the 4000 K light of the 3000 K model.
It is expected that the city will complete the installation of the led next month, but the led will be 3000 K instead of 4000 K.
Coogan knows that the debate on the health risks of LEDs is continuing.
But he did not want to be on the wrong side of history.
\"I don\'t want to find out in the next 10 or 15 years that we put our people at risk for health,\" Coogan said . \". —