Ever since the early days of natural gas escaping volcano leaks through bamboo pipes to serve as street lamps for ancient Peking in 500 BCE and lamps filled with vegetable oil in Ancient Rome, street lighting has been an essential way to combat the darkness that threatens to put an end to our day. As resources meant to encourage safety through visibility and deter crime, street lights have seen a significant amount of development over time through innovations in electricity and energy usage for illumination. This is reflected in current street lights.
The long period of street light use has allowed for perfection of the poles that support these luminaires. ASTM C1089-19 – Standard Specification for Spun Cast Prestressed Concrete Poles covers spun cast prestressed concrete poles for use as structural supports meant for not only street lights but also those used for traffic signals and electric transmission, distribution, and communication lines. This standard calls for specifications of the cement, aggregate, water, admixture, and steel used in the pole, in addition to tolerances and load bearing procedures.
As for the lights themselves, several ANSI C136 standards provide appropriate guidelines for their construction and maintenance. The latest revision of ANSI C136.15-2015 – Roadway and Area Lighting Equipment – Luminaire Field Identification provides a uniform method for identifying the type and wattage rating of a luminaire used for roadway and area lighting. Additionally, ANSI C136.16-2014 – Roadway and Area Lighting Equipment – Enclosed, Post Top-Mounted Luminaires gives the dimensions and maintenance needed for most kinds of street lights, as long as their center of mass is over the mounting tenon.
|Cobra Head Street Light|
Since one of the primary purposes of street lights is to prevent crime and ensure security during the hours of the night, it is incredibly important to prevent vandalism of the luminaires. As addressed in ANSI C136.34-2014 – Roadway and Area Lighting Equipment – Vandal Shields for Roadway and Area Lighting Luminaires, vandal shields can prevent vandalism of a street light that could potentially bring it to the point of destruction. The testing of the vandal shield that the standard calls for can vary with each example, depending on the specific protection that the streetlight requires. For example, this could include needs like flame and bullet resistance. These shields, while being securely installed, must also be removable for cleaning the luminaire.
While these standards give general guidelines on the construction and maintenance of luminaires, they do not address their specific design, which is often determined by the municipality or city in which the street lights are being installed. The type and placement of street lights is determined as part of many cities’ urban planning procedures, with support from the aforementioned guidelines. For example, in New York City, the standard is the Cobra Head luminaire, which is maintained by the NYC Department of Transportation and used for street and pedestrian lighting.