In practice, the precision of results of repetitive chronic tests is considered acceptable if the NOECs vary by no more than one concentration interval above or below a central tendency.
As long as the NOECs stay within a particular range, the results of repeated chronic testing will be considered precise enough.
An important town in Roman Gaul, replacing Lyon as capital toward the end of the Empire, Arles boasts a very well-preserved amphi?­theater (arynes), seating over 20,000 in the days of the gladiators.