The Research Council on Structural Connections (RCSC) currently recognizes four approved ways to control the tightness of structural bolts in a production environment. They are: 1. Turn-of-nut method; 2. Calibrated wrench method; 3. Direct tension indicator method; and 4. Twist-off bolt method. Below is a checklist of information on all four of these methods. Note that some specifications described in the following content may not be the same as the specifications followed by your agency. Always check with your State agency’s standards and specifications when using these guidelines.