Full Breakdown
Seoul Implements New Brightness Standards for Outdoor Billboards
4/1/2026, 7:11:34 AM
Introduction of Brightness Guidelines
On March 31, 2023, the Seoul Metropolitan Government announced the establishment of the first comprehensive guidelines in South Korea aimed at regulating the brightness of large outdoor LED billboards. These new standards will take effect on April 1, 2023, and apply to displays measuring 30 square meters or larger. The guidelines set daytime brightness limits at 7,000 candelas per square meter (cd/m²) or lower, while adjusting night-time standards based on billboard size and time of day.
Findings from the Survey
The guidelines were developed following a survey of 52 major billboards conducted between January and March 2023. The survey revealed a significant variation in daytime brightness levels, ranging from 1,448 cd/m² to 14,000 cd/m², with a median of approximately 7,000 cd/m². For night-time measurements, brightness levels varied from 100 cd/m² to 1,500 cd/m², with a median of about 400 cd/m². The new recommendations aim to reduce glare and visual discomfort for residents while ensuring adequate visibility for advertising.
Specific Brightness Standards
Under the new regulations, medium-sized billboards (30 to 225 m²) must maintain brightness below 500 cd/m² from one hour after sunset until midnight, and below 400 cd/m² thereafter. Large billboards (over 225 m²) are required to stay under 400 cd/m² until midnight and 350 cd/m² after midnight. These adjustments are designed to enhance urban aesthetics, improve citizen comfort, and promote energy savings of approximately 15%.
Content Operation Guidelines
In addition to brightness limits, the Seoul Metropolitan Government has introduced content operation guidelines to minimize visual fatigue. These guidelines recommend reducing the use of high-brightness white backgrounds in static images, employing lower-luminance color schemes, and implementing gradual transitions rather than abrupt brightness changes. The city advises against repetitive flashing and intense strobe effects.
Official Statements & Responses
Choi In-gyu, head of the city’s design policy division, emphasized that the new standards are not a blanket regulation but a targeted adjustment to curb excessive brightness. He stated, “This is a rational improvement by adjusting excessive brightness, taking into account both advertising readability and citizens' visual fatigue, as well as enhancing energy efficiency.”
Expected Impact
The implementation of these brightness standards is anticipated to improve the urban landscape and reduce discomfort for residents. Furthermore, the city plans to promote the adoption of automatic brightness adjustment devices that will regulate luminance based on ambient light conditions, particularly in designated outdoor advertising free zones.
Criticism & Opposition
While the new guidelines aim to balance advertising visibility with citizen comfort, some critics argue that the regulations may limit the effectiveness of outdoor advertising in high-traffic areas, potentially impacting businesses reliant on visibility.
What's Next
As the new brightness standards come into effect on April 1, 2023, the Seoul Metropolitan Government will monitor compliance and effectiveness, ensuring that the guidelines achieve their intended goals of enhancing urban aesthetics and reducing energy consumption.
