Where can you find the guidelines for railing design and testing?

Answer: C — AASHTO Guide Specifications for Bridge Railings

The AASHTO Guide Specifications for Bridge Railings is the correct source for guidelines regarding railing design and testing. This document is specifically developed by the American Association of State Highway and Transportation Officials (AASHTO) to address the unique requirements related to bridge railings, including performance, testing, and design considerations. It establishes the necessary criteria and standards to ensure that railings are effective in providing safety for vehicles and pedestrians on bridges. In contrast, while the ANSI Standards for Safety, the Federal Highway Administration Manual, and the American Concrete Institute Guidelines may cover various aspects of safety and structural design, they do not focus exclusively on the specifics of bridge railing design and testing as the AASHTO guidelines do. Thus, for accurate and precise information related to bridge railings, the AASHTO Guide Specifications is the authoritative reference.