GB5768.5-2017
Road traffic signs and markings—Part 5: Speed limit
道路交通标志和标线 第5部分: 限制速度
GB 5768.5-2017 is a current mandatory Chinese national standard for Road traffic signs and markings—Part 5: Speed limit. It appears in the Auto compliance cluster with a product safety focus and has an implementation date of Feb 1, 2018.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
GB 5768.5-2017 applies to the setting of speed limit signs and road markings on various road types, including highways, urban roads, and public areas accessible to social motor vehicles. This standard is mandatory for all traffic engineering and road design projects within China. It should be referenced by municipal planners, traffic engineers, and road safety facility manufacturers.
Technical requirements
This standard specifies the comprehensive requirements for determining and implementing road speed limits. It mandates that speed limit values must be based on the road's design speed and the 85th percentile speed observed under free-flow traffic conditions. The standard requires traffic engineering analysis to justify any speed limit that exceeds the design speed by 10km/h to 20km/h. The document outlines specific guidelines for the placement of speed limit signs, requiring them to be set at the starting point of the speed limit zone. It details the use of variable speed limit signs for adverse weather conditions (like fog or ice) and traffic congestion management. Specific layout requirements are provided for combined lane-specific and vehicle-type-specific speed restrictions, ensuring clear visual guidance for drivers. Additionally, the standard defines the requirements for pavement speed limit markings, which must be consistent with the corresponding overhead or roadside signs. It also references Appendix C for determining the minimum length of speed zones to ensure driver adaptation and safety.
Testing methods
The standard outlines evaluation procedures for determining appropriate speed limits, primarily relying on traffic speed distribution analysis. Key methodologies include collecting free-flow speed data under specific conditions (e.g., weekdays, dry weather, hidden observation points) to determine the 85th percentile speed. Engineers must calculate the 15km/h speed step (步距) to analyze the concentration of vehicle speeds and ensure the proposed limit aligns with actual driver behavior and road environment consistency.
FAQs
What products and scenarios are regulated under GB 5768.5-2017?
This standard applies to the setting of speed limit signs and markings on various roads, including highways, urban roads, and public areas. It is a mandatory standard for traffic engineering facilities in China.
How is the speed limit value determined according to GB 5768.5-2017?
The standard requires determining speed limits based on the road's design speed and the 85th percentile speed. It allows for speed limits to be set at, below, or up to 20km/h above the design speed, provided that a traffic engineering analysis is conducted.
Are there any significant updates from the previous version of GB 5768?
It partially replaces GB 5768-1999. The new version introduces detailed methodologies for determining speed limits using the 85th percentile speed, adds provisions for variable speed limit signs, and provides specific guidelines for combined lane and vehicle-type speed restrictions.
The summary above provides a high-level overview of GB 5768.5-2017. To ensure complete compliance for your traffic engineering projects or product implementations in the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 5768.5-2017 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Safety
- CCS
- R80
- ICS
- 03.220.20
- Competent department
- Ministry of Transport
- Technical committee
- Ministry of Transport
Relationships
Partially replaces:GB 5768-1999