Get expert guidance from our Product Specialists who match the right solutions to your project's requirements.
Written by Neil PetersonHighway lighting plays a crucial role in ensuring roadway safety by maintaining visibility during nighttime hours. While similar to street lighting, highway lighting serves broader coverage areas and requires different specifications.
Highway lighting fixtures help drivers safely navigate long stretches of road by illuminating vehicles, barriers, bridges, signage, and roadside hazards. Studies suggest that properly designed highway lighting systems may help reduce nighttime roadway incidents by up to 30%, although the effectiveness depends on proper installation, maintenance, and local conditions.
Important: All highway lighting installations must comply with local codes and regulations. Consult with qualified professionals for specific project requirements.
Quality highway lighting systems should provide the following benefits:
While highway lighting fundamentally improves visibility, simply installing the brightest available fixtures isn’t always optimal. Several factors affect lighting performance and safety.
As light levels decrease, visual detection capability becomes significantly impaired. Conversely, as light levels increase, vision and information detection improve substantially. However, optimal performance depends on more than just brightness levels.
Contrast plays a crucial role in visibility. Contrast refers to the brightness difference between objects and their background. Higher contrast levels make it easier to distinguish subjects from backgrounds.
Drivers typically perceive objects as dark forms against brighter backgrounds. However, excessively bright backgrounds can create glare, reducing contrast and detail visibility. The key is balancing adequate illumination with proper light angle and quality distribution.
LED highway lighting offers superior glare control compared to traditional technologies, while also helping reduce light pollution through better beam control and directional lighting.
Most LED highway fixtures feature lens systems that distribute light in rectangular patterns, directing illumination efficiently across roadway areas. LEDs are increasingly popular for highway applications due to their low operating costs, extended lifespan, and reduced maintenance requirements.
Metal halide fixtures generate light through metallic vapor combinations. While offering high initial lumen output, this output degrades relatively quickly with use. These fixtures also consume significant energy, resulting in higher electrical costs compared to LED alternatives.
HPS fixtures use sodium vapor to produce illumination. These fixtures contain small amounts of mercury, requiring proper disposal procedures in accordance with environmental regulations. While producing high lumen output, they experience rapid lumen depreciation and provide warm-colored light with limited color rendering capability.
HID fixtures produce light by exciting gases or metal vapors within enclosed tubes. While capable of high lumen output, they’re generally considered less suitable for highway applications due to fragility concerns and rapid lumen depreciation over time.
LED lighting is typically the preferred choice for highway installations. Key advantages include superior energy efficiency, extended operational lifespan, and reduced maintenance requirements compared to traditional technologies.
While initial LED fixture costs may be higher than conventional alternatives, the total cost of ownership typically favors LED due to:
Note: Actual savings will vary based on local energy costs, installation specifics, and maintenance practices. Consult with lighting professionals for project-specific cost analysis.
Conventional highway lighting systems use various mounting heights based on illumination requirements. Common mounting heights include 40, 45, and 50 feet, with standard installations using one luminaire per pole, while median-mounted configurations may employ two luminaires per pole.
Sample FDOT Illumination Requirements (requirements vary by location – verify current local standards):
LED high mast lighting systems utilize mounting heights of 80 feet or higher, with 120 feet being common for many installations. These systems can accommodate multiple luminaires per pole, with quantities determined by required illumination levels.
Large installations may feature 12 to 16 luminaires per pole. Luminaires connect to a lowering ring system operated by ground-level winches, allowing the entire fixture assembly to be lowered for maintenance using either installed electric motors or portable drill motors.
Sample FDOT High Mast Requirements (verify current local standards):
Overhead sign structures require dedicated lighting to ensure message visibility during both day and nighttime conditions. These systems provide critical information to drivers around the clock.
Recent developments in retroreflective sheeting technology allow signs to utilize vehicle headlight illumination for visibility. While these materials involve higher initial sign costs, they can reduce sign lighting infrastructure requirements and associated electrical installation expenses.
Major highway interchanges often feature wide overpasses requiring adequate lighting for roadways beneath the structures. Underdeck lighting typically uses either pier cap-mounted or pendant-hung fixtures attached to bridge structures.
Pier cap fixtures are required when bridge piers are located within 15 feet of travel lane edges. Pendant-hung fixtures mount to bridge deck undersides, with positioning such that approximately 50% of the luminaire extends below the bridge beam level. Fixtures should not attach directly to bridge girders.
Underdeck lighting levels should match adjacent roadway lighting standards to maintain consistent visibility.
Professional Installation Required: Highway lighting involves complex electrical and structural considerations. Work with qualified lighting contractors experienced in highway applications.
Effective highway lighting serves multiple safety functions: maintaining roadway visibility, enabling sign reading, and increasing driver comfort during nighttime travel. Research indicates that properly designed systems can contribute to accident reduction and improved overall road safety.
LED technology offers significant advantages for highway applications, including:
While LED fixtures may involve a higher initial investment compared to traditional technologies, the combination of energy savings and reduced maintenance typically provides a favorable return on investment, particularly important given the specialized equipment and labor required for highway lighting maintenance.
Important Disclaimers:
Neil Peterson is Chief Executive Officer at LED Lighting Supply. He has been active in the LED industry for over 10 years and is responsible for product planning and management as well as revenue and operations at LED Lighting Supply. Much of Neil’s time is focused on working with customers on large commercial and industrial lighting requirements. When not working, he enjoys family time, camping, fishing, and sports.
