Never heard of a sector 7G. I was a Nuclear Maintenance Machinist for over 26 years, and there were just a few really high rad areas that no one went in. Other that that I have been in all areas. But back on topic.
The plant used a lot of different style bolt locking devices and all of them called for clean threads, lube and a torque. All primary systems called for a QC witness sign off on the procedure. To this day I use never seize on everything I work on like the lug nuts on my vehicles and never have any issues with bolting coming loose. Most of the plant piping just used flat washers and torque to spec.
One other thing, the grade of the bolts also determines the torque. If you take a grade 8 bolt and torque to a lower grade bolt spec, it will not get the proper torque to stretch the grade 8 bolt. And if you take a lower grade bolt and torque it to grade 8 bolting, you over stretch the bolt and thus risk weakening it.
Don