How does the special inspector verify that bolts, nuts, and washers meet A325 or A490 specifications?

The correct approach for verifying that bolts, nuts, and washers meet A325 or A490 specifications is through manufacturer certification. This certification confirms that the materials were produced according to the required specifications and standards. It provides documentation that includes the grade and type of bolts, nuts, and washers, along with any relevant test results, ensuring that the components meet the necessary performance criteria for structural use.

Manufacturer certification is essential in the construction industry, particularly for structural steel connections, as it provides an assurance of quality and compliance with established standards. This documentation helps special inspectors confirm that the materials conform to the specifications without needing to perform exhaustive tests on every individual component.

While visual inspection can help assess the general condition or ensure correct assembly, it cannot determine whether the materials meet the strength and performance requirements set forth in the specifications. Material testing and field testing involve more extensive processes and measurements, which may not always be practical or necessary for every component, especially when proper certification is available and sufficient. Thus, relying on manufacturer certification is the most efficient and reliable method for verification in this context.