It does this by checking 3 possible indicators:
- Norns older than 9 hours may be immortal.
- Norns with 2 or more toxins in their body over 95 may be immortal.
- Norns that reached adult before they were 30 minutes old are probably fast-agers.
If any of these checks are matched then a "boing" sound will be heard and the Norn's name that is displayed above the NoK will have 1 or more extra letters added in front of it followed by a ! as follows:
- O = Old
- T = Toxins
- A = Aging
Norns are checked every 5 minutes and are forced infertile every 20 seconds. Infertility cannot be guaranteed, as fertility rises constantly with time, though it should greatly reduce the chance of pregnancies. There is also the possibility that an immortal/fast-ager will warp in and reproduce between the Norn of Infertility's checks."