1、NEMA Standards PublicationNational Electrical Manufacturers AssociationNEMA LSD 55-2017Outdoor Lighting and Human/Animal Factors: An Industry EvaluationA NEMA Lighting Systems Division Document LSD 55-2017 Outdoor Lighting and Human/Animal Factors: An Industry Evaluation Prepared by: NEMA Lighting S
2、ystems Division National Electrical Manufacturers Association 1300 North 17th Street, Suite 900 Rosslyn, Virginia 22209 The requirements or guidelines presented in this document, a NEMA Lighting Systems Division white paper, are considered technically sound at the time they are approved for publicat
3、ion. They are not a substitute for a product sellers or users own judgment with respect to the particular product discussed, and NEMA does not undertake to guarantee the performance of any individual manufacturers products by virtue of this document or guide. Thus, NEMA expressly disclaims any respo
4、nsibility for damages arising from the use, application, or reliance by others on the information contained in these white papers, standards, or guidelines. The opinions expressed in this statement represent the consensus views of the member companies of the Lighting Systems Division of the National
5、 Electrical Manufacturers Association. The members of the Lighting Systems Division manufacture indoor and outdoor lamps, which include incandescent, fluorescent, light-emitting diode, and solid-state lamps, lighting fixtures, and lamp ballasts. 2017 National Electrical Manufacturers Association. Al
6、l rights, including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, and the International and Pan American copyright conventions. NEMA LSD 55-2017 Page 2 2017 National Electrical Manufacturer
7、s Association Introduction Outdoor lighting at night provides many obvious and accepted benefits to society, including the ability to safely travel on roadways, facilitate commerce, enable outdoor activities such as recreation, provide for the lighting of architecture and landmarks, and provide for
8、social and personal security. NEMA Lighting Systems Division members have significant concerns with published materials that portray any type of outdoor lighting as contributing to a negative nighttime environment without giving due consideration to all the factors involved and the existing body of
9、research. The views of the Lighting Systems Division members are shaped by the principle that, regardless of the issue, public policy that relates to technical issues should always be based on sound scientific evidence and not built on speculation or conjecture. Factors Influencing NEMAs Point of Vi
10、ew NEMA Lighting Systems Division members share the same fundamental concerns as many do regarding the need for energy conservation, dark sky preservation, mitigation of potential ecological impacts of outdoor lighting, and the growing body of research that seeks to understand and explain the effect
11、 of the circadian cycle on human and animal health. NEMA Lighting Systems Division members support ongoing efforts by various agencies and organizations, such as the Illuminating Engineering Society (IES), International Dark-Sky Association (IDA), and the United States Department of Energy. Members
12、also support initiatives that will minimize the amount of outdoor electric lighting needed to achieve functionality that reduces unnecessary stray light. This includes the likelihood of light trespass, nighttime sky glow, and excess energy consumption associated with inefficient lighting. NEMA light
13、ing member companies are committed to providing improved lighting solutions that help achieve these objectives. For instance, members of NEMAs Lighting Systems Division were actively involved in the development of the IDAs Model Lighting Ordinance that promotes quality lighting standards for municip
14、alities. NEMA members also continue to work in collaboration with the IESs Roadway Lighting Committee regarding this general topic. Many NEMA members have been aggressive in developing and promoting the types of outdoor lighting products and practices that are endorsed or recommended by IDA, includi
15、ng sharp cutoff luminaires and lighting controls. NEMA members also support the adoption of sensible generic outdoor lighting ordinances and specific requirements that are sometimes tailored to localities that have particular concerns, such as disruption of sea turtle habitats. Collaborative activit
16、y among interested parties based on sound scientific evidence and best practice is the best way to achieve outdoor lighting that will benefit global climate, ecology, astronomy, and, potentially, human health. Many of the subjects pertinent to the issue of light exposure and its effects on the day/n
17、ight cycle in humans and animals are scientifically complex, and are not yet fully understood, even by the scientific communitysuch that specific technical recommendations, particularly regarding outdoor light source spectral content, cannot yet be developed, much less propounded. There are many cur
18、rent efforts to establish a technical requirement regarding spectral content address scientific questions that are not yet completely understood. NEMA Lighting Systems Division members contend that technical recommendations that have the potential to impact lighting products, emerging technologies,
19、outdoor lighting design and architectural practices, lighting codes, and legislation must be based on expert consensus after full scientific discourse and peer review. By definition, sound science must include adequate replication of results and validation of theories and hypotheses in the form of s
20、upporting measurements and datanot simply in a laboratory environment, but also under real world field conditions. Only in this manner can sufficiently detailed technical and mathematical relationships be NEMA LSD 55-2017 Page 3 2017 National Electrical Manufacturers Association. developed that can
21、form the basis of actionable practices and standards. Any guidance should be based on scientific studies. Some proposals oversimplify the ecological tradeoffs that are inherent with any proposal to limit outdoor lighting to a certain correlated color temperature (CCT). Such recommendations do not re
22、cognize the inconsistencies of such a spectrum choice, for instance, that long wavelength “red” light purportedly may disturb certain bird migrations while short wavelength (i.e., blue) light distracts sea turtles. How is such a trade-off to be reconciled between species? The topic of lighting color
23、 is complex and involves many factors beyond CCT. Thus, promoting specific CCTs to advance a particular outdoor lighting policy may have unintended consequences on overall lighting quality and other concerns of public policy such as safety and security. Outdoor lighting products, technologies, and p
24、ractices have been strongly grounded in sound engineering practices driven by the careful measurement and analysis of data. This focus on data-driven methods must continue, especially if future technical recommendations are expected to drive change in how outdoor lighting is practiced credibly, how
25、emerging technologies such as solid state lighting are treated, and how future product offerings are configured. Communities today are focused on promoting quality outdoor lighting, but the issues are not simple. A careful balance of controlling light pollution, excessive lighting infringing on resi
26、dential property, and energy use while addressing issues of visual acuity and safety/security requires consideration of not only the lighting equipment installed but also the design and layout of the lighting equipment on a site. These issues are typically best addressed by local community ordinance
27、s rather than regional or national regulations. NEMA LSD 11-2010 Outdoor Lighting Issues and Quality Lighting Applications identifies specific lighting issues, defines correct lighting terminology, and provides straightforward technical guidance applicable to outdoor lighting installations in the U.
28、S. The publication is intended to be used by anyone dealing with the selection, installation, or management of outdoor lighting systems. The key recommendations are: NEMA Lighting Systems Division members fully support many outdoor lighting recommendations currently being advocated such as: a. use o
29、f light control options such as motion sensing, time-of-night dimming, and stepped power switching (including an appropriate use of complete shutoff for some applications) to conserve energy; b. luminaire shielding to curtail excessive uplight, glare, and light trespass; c. limiting illumination to
30、the specific task or targeted area; and d. designing for the minimum light levels and connected power load necessary for the task. The Color of Light NEMA Lighting Systems Division members do not believe there is sufficient data to recommend that outdoor lighting systems be limited to any CCT. Outdo
31、or lighting products typically emit a broad spectrum from violet to red that is combined to make white light. The spectral distribution can be more heavily weighted toward the blue or red, or it can be more heavily weighted to the middle of the spectrum to produce yellow or green light. While the NE
32、MA LSD 55-2017 Page 4 2017 National Electrical Manufacturers Association technology producing the light can change from fluorescent to high-pressure sodium, to metal halide, or to LED, the light energy is all the same, regardless of the source. There is no difference between the short wavelength blu
33、e light energy produced by a fluorescent lamp, or a metal halide lamp or an LED source; it is all radiated short wavelength blue light. The lighting industry characterizes the color of white light using the term CCT. Color temperatures of common light sources used outdoors can range from approximate
34、ly 2000K to 7000K. Lamps that have a 2000K color temperature, such as high-pressure sodium, look very yellow. Lamps that have color temperature of 7000K look very blue. Lamps that have CCT between 3000K and 4000K have a balanced color spectrum and tend to look white. 3000K lamps have a slightly warm
35、er (yellow) appearance than 4000K lamps. A single color temperature is not appropriate for all applications. Each application must be evaluated on a case by case basis to select the most appropriate color temperature for that application. Proposals for outdoor lighting that suggest that limiting the
36、 CCT to a maximum of 3000K in all cases are not supportable and are focused on resolving issues for specific applications to the detriment of other applications. The Case for Only Using Higher Color Temperature Lamps Some groups have made the case to only use higher color temperature sources when ou
37、tside, e.g., 4000K, 5000K, or higher. Their point is that light sources with higher CCT have more energy in the short wavelength (i.e., blue) part of the spectrum which is better seen by the human eye at the very low light levels typical of outdoor applications. The argument is that use of high colo
38、r temperature sources, therefore, can improve human reaction time, and improve energy efficiency, safety and security. Following this logic, they argue that using such sources may also allow designers to reduce light levels, rather than using lower color temperature sources to achieve the same visua
39、l lighting effect. The Case for only using Lower Color Temperature Lamps The American Medical Association Community Guidance issued on June 14, 2016, suggested only using lower color temperature sources of 3000K or less over concerns about circadian rhythm effects. They argue that the short waveleng
40、th radiation, (i.e., blue light) found in higher color temperature sources can potentially suppress melatonin and negatively affect sleep cycles. However, it has been documented in several studies that such effects can only occur with a high exposure level and a long exposure time to blue light. The
41、 required exposure to blue light for the retina is extremely unlikely to be achieved under outdoor lighting conditions where outdoor light levels are very low, and users are generally exposed to outdoor lighting for a very short period. In contrast, people with seasonal affective disorders (SAD) who
42、 try to suppress melatonin levels in the morning are often told to sit next to a lighting fixture containing high-intensity, high CCT light sources for 30 to 60 minutes. The Lighting Research Center (LRC) has indicated that CCT is not the correct metric to predict blue light content. Rather, it is r
43、ecommended that the appropriate metric must consider spectral power distribution (SPD) along with light level expressed in photopic lux.11LRC Response to the 2016 AMA Report on LED Lighting, http:/www.lrc.rpi.edu/resources/newsroom/AMA.pdf LRC Webinar on Blue Light - Response to AMA, https:/ this is
44、 why manufacturers offer products with a wide range of color temperatures options so users can select the product that best meets their needs. Unlike traditional outdoor lighting sources such as high-pressure sodium lamps that are only available at lower color temperatures, or metal halide lamps tha
45、t are mainly available at high color temperatures, new LED technology provides a wide range of color temperature choices. American Medical Association Guidance The American Medical Association issued a report for Community Guidance Regarding Street Lighting on June 14, 2016. In this report, the AMA
46、Council on Science and Public Health expressed concern regarding the impact of LED street lighting on glare, disruption of nocturnal species and disruption to the human circadian system. Many media outlets reported on this AMA guidance and presented conclusions that were either inconsistent with the
47、 guidance or extended beyond the body of scientific research. Various lighting authorities have provided public statements to clarify the use of LED lighting and result from lighting research. (See Appendix A) The AMA guidance when taken into consideration with the responses from various lighting au
48、thorities, clearly articulates that LEDs offer by far the most energy efficient method for street lighting. There is also consensus that when properly designed and applied, LED lighting provides many advantages. These benefits, which are true for street lighting as well as all outdoor site and area
49、applications, go beyond energy savings and can enhance peoples experience. Health Impact Considerations of AMA GuidanceDisruptions to Circadian Rhythm and Melatonin Production Several responses to the AMA guidance are critical of the AMAs assertion that LEDs present a health risk, particularly as it pertains to blue light levels. For example, the LRC indicates that the CCT metric ignores nearly all of the important factors associated with light exposure (amount, duration, timing) and is only relevant to a single biological response (
