I called the state library reference desk and just flat asked. After a slow start, I learned that:
(a) _all_ state rules expire after 8 years
(b) most state rules have to exist in order to implement federal law (like, water quality kinda stuff)
(c) there are no library rules and haven't been for close to a decade
(d) there are unlikely to ever be library rules again
Since the state doesn't give any money to libraries and has no other enforcement authority, and it costs money to implement rules (public hearings and so forth), the last batch of rules lapsed and were never replaced.
So the next time someone says, state whatever sez we're supposed to, I can just blow them a raspberry and possibly thumb my nose at them.
Respectfully, of course.
Who knew? It does free us up to use other guidelines (from national organizations, other states, etc.), since there isn't anything more directly applicable.