We usually have to use a combination of all the items you mentioned.
We have signage indicating not to touch any of the objects as well as physical, yet discrete barriers.
The more fragile items are typically placed in view of the visitor services manager (me).
For our textile shows, we use a stanchion with a sign that has a hand with a red circle and a line going through it and a short few sentences saying that the oils from our hands are extremely damaging to textile art. Its a good way for kids to SEE not to touch and for adults to TEACH/REMIND their kids (selves) why touching art can be damaging. This can be used for all items in the museum as well.
Our museum is in the process of developing signage for letting people know that there are security cameras in use (due to a recent vandalism case). We do not want to be intruding or display negative images about big brother so I think we can just use an "eye" icon or plain text saying that cameras are in use.
I hope this info serves you well!
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Cassidy Tucker
Visitor Services and Retail Coordinator
Missoula Art Museum
Missoula MT
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