Content warnings are controversial for good reason. Done poorly, they moralize, stigmatize, and reinforce assumptions about the identity of the museum visitor. But trauma is real and it's fair to expect museums to try not to retraumatize people. Here are some guidelines I use for crafting and employing content warnings in museums.
When to use a warning
When considering whether to include a content warning, I recommend centering the wellbeing of the people most likely to be negatively impacted by the content and taking into consideration the role of systemic oppression.
For example, you might be concerned that a warning on a room of lynching photos might deter the white people who you think most need to see them, but prioritize the experience of a Black visitor who may not have the capacity for that content today. Use a content warning.
You might be concerned that some visitors will be offended if they come across artworks depicting trans people if there is no warning, but prioritize the experiences of queer visitors who will feel stigmatized. Do not use a content warning.
Effective content warnings
Effective content warnings do not dictate how visitors should decide to view an exhibit but instead describe the content and let visitors make up their own minds.
Content warnings should be descriptive. Don't use vague language. Tell visitors what to expect. “Work that some might find upsetting” and “strong adult themes” don't set a clear expectation. Instead, spell it out: eg. "discussion of suicide” or “depictions of sex acts.”
Content warnings should not speculate who the content is or is not suitable for. Suggesting content is not for kids sets visitors up for scrutiny from others if they do bring their kids into the gallery. Remember, not all adults visiting with children are parents.
Don't describe visitors as sensitive.
The best content warnings I've seen in museums:
Give a detailed description of what to expect in the gallery
Avoid making assumptions about who the content is or is not for
Offer alternative routes should they wish to avoid this particular content