Relic and data site scanning

Is there a relation between the type of relic or data site and their scanning diff level? I noticed that usually the ‘safe’ locations are Level I and II and the ‘unsafe’ ones (Forgotten, Unsecured) are Level III, but I am not sure if this is a rule, as I don’t remember seeing it anywhere mentioned.

There is a relation.

Likewise, Combat Gas sites in k-space are more difficult to probe down then mining gas sites.

The level I and II are always ‘safe’ and the ‘unsafe’ sleeper sites are always level III … but … there are level IIIs that are safe as well.