Hi Alyssa,
Content warning placement and prevalence may depend on the type of content you're warning about, or the type of museum you're working with. It's becoming more and more common for museums (especially anthropology-based museums) to feature content warnings for human remains. These are often repeated in several locations: at the front of an exhibit, at the door to a gallery within an exhibit, and prominently on a given case. Some museums also feature a content warning for human remains at the admissions desk, as there are varying levels of cultural sensitivity and some visitors may be fine avoiding a room or pathway while others may not want to be in a building that contains human remains at all.
Some museums will place disclaimers/content warnings with displays or online galleries of ethnographic photos to indicate that they were often staged by Western anthropologists. I've also seen language warning that photos contain images of deceased individuals, which is important to know for some visitors from various Indigenous communities. Many anthropology collections also have a disclaimer/content warning prominently placed on online collections websites indicating that legacy records often used language to describe other cultures or communities that may be inappropriate or inaccurate today.
I've also seen content warnings for sexual content (very rarely and usually only for very explicit, intentionally sexualized content; not for nude figures in non-sexual positions, for example) at the exhibit or gallery level, and for extreme violence (e.g., the SI NMAAHC has a gallery-level warning before graphic photos from lynchings).
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Lauren Cooper
Exhibition Interpretation Specialist
The Huntington Library, Art Museum, and Botanical Gardens
San Marino, CA
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