Click for next page ( 5


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 4
5 ENERGY POLICY ACT OF 2005 The net effect of the Energy Policy Act of 2005 is that it effectively eliminates the use of incandescent traffic signal The Energy Policy Act of 2005 Title I, Subtitle C, Sec- modules on new installations and facilitates the transition of tion 135 (z), applies to the manufacture and import of traffic traffic signal modules to more energy efficient LED technol- signal and pedestrian modules (3). The sections of the EPACT ogy by placing energy consumption criteria on red and green 2005 relevant to traffic signals appear below. LED traffic signal modules. The EPACT 2005, Title 1, Sub- title C, Section 135 (z) applies to Traffic Signal and Pedes- (a) DEFINITIONS-- (43) The term "traffic signal module" means a trian Modules manufactured on or after January 1, 2007. This standard 8-inch (200mm) or 12-inch (300mm) traffic signal act effectively overrides earlier Energy Star requirements for indication that-- LED traffic signal modules. (A) consists of a light source, a lens, and all other parts necessary for operation; and (B) communicates movement messages to drivers through It should be noted that the focus on green and red indica- red, amber, and green colors. tions resulted from their longer duty cycle. The early cost of (b) TEST PROCEDURES-- LEDs made it difficult to justify the electrical savings from (11) Test procedures for traffic signal modules and pedes- the change-out of the yellow indication. As costs have come trian modules shall be based on the test method used under the Energy Star program of the Environmental Protection down and practical considerations of having to maintain two Agency for traffic signal modules, as in effect on the date of different types of technology have come into play, LEDs are enactment of this paragraph. now typically used for all colors. (c) STANDARD SETTING AUTHORITY-- (z) TRAFFIC SIGNAL MODULES AND PEDESTRIAN MODULES-- ITE LED SPECIFICATIONS Any traffic signal module or pedestrian module manufac- tured on or after January 1, 2006, shall-- (1) meet the performance requirements used under the Energy ITE released the LED purchase specification, "Vehicle Traf- Star program of the Environmental Protection Agency fic Control Signal Heads Part 2," in 1998 (4). The VTCSH for traffic signals, as in effect on the date of enactment Part 2 was released as an interim purchase specification to of this subsection; and meet the needs of public agencies in light of the rapid expan- (2) be installed with compatible, electrically connected signal control interface devices and conflict monitoring systems. sion of LEDs into traffic signal modules. The VTCSH Part 2 (d) GENERAL RULE OF PREEMPTION-- was intended to provide interim specifications while further (B) is an amendment to a regulation described in subpara- human factors and photometric tests were completed on LED graph (A) that was developed to align California regulations traffic signal modules. Studies on the effects of luminous to changes in the Institute for Transportation Engineers standards, entitled "Performance Specification: Pedestrian intensity, chromatic variation, and degradation of light out- Traffic Control Signal Indications." put needed to be fully understood before the ITE specifica- tion could be updated. Span wire-mounted LED traffic signal ENERGY STAR REQUIREMENTS modules were implicitly excluded from the VTCSH Part 2 as luminous intensity was not addressed at an adequate variation The Environmental Protection Agency Energy Star Program of vertical and horizontal angles to encompass this mounting Standard in place at the time of EPACT 2005 became the cri- technique. teria for traffic signal modules. The energy efficiency crite- ria for Energy Star Qualified Traffic Signal Modules appear ITE replaced the VTCSH Part 2 in June 2005 with a per- in Table 1. formance specification published under the name "Vehicle Traffic Control Signal Heads: Light Emitting Diode Circular TABLE 1 Signal Supplement" (VTCSH-LED) (1). Full adoption of the ENERGY EFFICIENCY CRITERIA FOR ENERGY STAR new ITE 2005 VTCSH-LED occurred 1 year from the effec- QUALIFIED TRAFFIC SIGNAL MODULES tive date of the specification making the 1998 VTCSH Part 2 obsolete. The VTCSH-LED supplement states that agencies Maximum Nominal should use this specification as a minimum performance Wattage Wattage Module Type (at 74C) (at 25C) specification or document alternative requirements based on an engineering study. 12-in. Red Ball 17 11 8-in. Red Ball 13 8 Arrow modules are addressed in an ITE-approved speci- 12-in. Red Arrow 12 9 fication entitled "Vehicle Traffic Control Signal Heads-- 12-in. Green Ball 15 15 Part 3: Light Emitting Diode (LED) Vehicle Arrow Signal 8-in. Green Ball 12 12 Modules--A Purchase Specification." ITE also adopted 12-in. Green Arrow 11 11 specifications on March 19, 2004, entitled "Pedestrian Traf- Combination Walking Man/Hand 16 13 fic Control Signal Indications--Part 2: Light Emitting Diode Walking Man 12 9 (LED) Pedestrian Traffic Signal Modules." While these Orange Hand 16 13 pedestrian signal specifications are approved ITE standards,