The recommendations for using these guidelines strongly depend on the specific background and purpose of the reader. Experts already familiar with the basics for LED street lighting for example may directly check the specific PremiumLight-Pro recommendations for procurement criteria in chapter .
Experts less familiar with the basics may first of all browse through chapters 2 and 3, which cover the basic information relevant for understanding the procurement criteria, including the important quality and efficiency aspects for street lighting and the standard EN 13201. Chapter 5 finally showcases some of the selected best practice examples for LED street lighting.
Efficient high quality street lighting solutions based on LED technology need to be based on sound quality, efficiency and safety criteria. The following chapters provide an overview of the most essential criteria and explain specific aspects of LED technology.
DESIGN STANDARDS AND GUIDELINES
The Design Standards and Guidelines manual was initiated in June of 1997 to establish uniform guidelines and practices to be followed by engineers in designing street lighting systems. The purpose of the manual is to provide designers with direction, set standards and policy.
The goal of this manual is to provide street lighting engineers with clear direction in order to increase productivity by streamlining design procedures, and increase efficiency by establishing a centralized source of up-to-date reference for current standards and procedures.
In addition, this package will enhance the quality of design and empower the Street Lighting Engineering Associate III’s, Division and Senior Engineering Managers. The manual contains the following: • Guidelines for levels of approval of street lighting design recommendations and final plans. • Illumination standards for various areas and roadways (including pedestrian ways). •
Equipment Selection Standards • Bureau policy in relation to various design requirements. • Approved Planning Routes and areas. • Design Recommendation checklist and final plan checklist. This manual and directive will be updated on a semi-annual basis by the Senior Manager in charge of the design divisions.
STREET LIGHTING ASSOCIATE III • Street Lighting relocation projects (normally referred to as “A” or “X” permit projects) • Encroachment permits • Sewer and Storm repair plans requiring BSL approval.
• Projects with less than 20 poles of the following selection: 40’ Davit, CD-953, CD-929, Gardco Semi-Spherical, CD-851 and CD-808Z, and that fall within the parameters of the Equipment Selection Guidelines. • Pedestrian Tunnel Closure Projects. DIVISION ENGINEER APPROVAL • Projects 21 to 75 poles of the following selection: 40’ Davit, CD-953, CD-929, Gardco Semi-Spherical, CD-851 and CD-808Z, and that fall within the parameters of the Equipment Selection Guidelines.
• Upgrade projects (E& C and STM) with NO Proposition 218 impact. SENIOR ENGINEERING MANAGER APPROVAL • All BSL advertised projects. • Projects greater than 75 poles on streets where design is matching an existing system.
RECOMMENDED ILLUMINATION LEVELS FOR MISCELLANEOUS SYSTEMS The following is a summary of the lighting levels for special situations, as recommended by IES Standard Practice for Roadway Lighting, RP-8, 2000.
Minimum average illumination level for stairways with low Pedestrian Conflict Areas and on a medium Density Residential are 4 Lux (0.4 fc) with uniformity ratio of 4:1. Also refer to DG-5-94 for additional criteria.
Minimum average horizontal illumination Bikeways (Class 1) with High Pedestrian Conflict Areas are 10 Lux (1.0 fc) with uniformity ratio of 4:1. Also refer to DG-5-94 for additional criteria.
Crosswalks traversing roadways in the middle of blocks without signalization should be provided with additional illumination. The average illumination level in the crosswalk area should at least be equal to that provided at the intersection of two major streets; i.e., about 34 lux (3.4Fc). The uniformity ratio should be no more than 3:1.
Illumination level over track area, starting 100 feet (30 meters) before the crossing and ending 100 feet (30 meters) beyond the crossing, should be in accordance with Table D1 and table D2 on RP8-2000, but never less than 9 Lux (0.9FC). The uniformity ratio should be no more than 4:1. Refer to DIRECTIVE #397.
Around Public Facilities (i.e. schools, parks, recreation centers, etc.)
Illumination levels for the surrounding roadways should be considered as Medium Pedestrian Conflict area and follows the IES guidelines. The uniformity ratio should be no more than 3:1.
Illumination levels for parking lots should have an average illumination level of 22 Lux (2.0 fc) for LADOT open parking lots and uniformity ratio of 3:1. Also refer to RP-20-98 for additional criteria.
The main objective in tunnel lighting design is to provide a lighting system for a given tunnel meets the visibility requirements for day and night conditions. The following issues need to be addressed when designing tunnel lighting for both daytime and nighttime values: threshold zone, transition zone, and tunnel interior zone. Many factors determine luminance values for tunnel lighting design. Refer to IESNA RP-22, 1996 for classification of your tunnel and appropriate lighting levels.
Cultural Historical Structures
All designers shall be aware of the Historical Cultural Monuments listing as published by the Cultural Affairs Department. Bureau district maps should refer to this document for all Historical Cultural monuments. In accordance with the State Historical Building Code these structures ma be restricted in modifications to electroliers such as different spacing or height. In these cases the Bureau shall try to achieve the highest level possible not to exceed IES standards.
Bus Stop Facilities
Illumination levels over a Bus Stop area should have an average illumination level of 25 lux (2.5 FC).The uniformity ratio is at 3:1 .Lighting levels should be in addition to the level provided by the regular street lighting system. Typically these facilities are 80’ in length and are provided with three lighting fixtures attached at 15’ height. Also refer to RP-33-99 and G-1-03 for additional criteria.
Architectural Lighting Design Considerations
The purpose of an architectural lighting system is to highlight, enhance, and accentuate the outstanding architectural features of a bridge. Architectural lighting projects are subjective to artistic impressions or interpretations.
There are no current City adopted lighting standard or IES requirements for illumination levels for the bridge’s handrails, arches, columns, approach gates, and piers. Considerations for exterior lighting (as suggested by IES Lighting Handbook, 8TH Edition, Chapter 22) design include: • COMMUNITY THEMES (in architecture and in lighting) • LIGHTING ORDINANCES (light Pollution and light trespass) • SURROUNDING BRIGHTNESS (bright downtown industrial)
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