How many complete fastener assemblies must be checked on-site in the tension calibrator?

The correct number of complete fastener assemblies that must be checked on-site using the tension calibrator is three. This requirement is in place to ensure the accuracy and control of the bolt installation process, which is critical for the integrity of the structural assembly.

By checking three complete fastener assemblies, you are effectively verifying the torque and tension being applied during the installation. This helps in affirming that the tensioning tools and procedures are functioning correctly and that the fasteners are achieving the required tension as specified on the engineering drawings or project specifications. The use of three assemblies allows for a reliable assessment of the tool's performance, as it provides a sufficient sample size to account for any variations in installation techniques or equipment.

This practice not only promotes consistent quality control during construction but also adheres to recognized standards and guidelines within the industry that dictate the necessity of verifying tension in multiple assemblies to mitigate the risk of structural failure. Checking fewer than three assemblies would not provide a comprehensive enough understanding of the tool's performance, while checking more than three may be unnecessary for most applications unless specified otherwise.