In US museums, why are backpacks only allowed to be carried on one shoulder?

Question

Many US museums permit backpacks only when they are carried on one shoulder. Here are some examples:

• Philadelphia Museum of Art:

  Backpacks and large bags must be checked. Smaller bags may be carried on one shoulder or handheld.

• The Nelson-Atkins Museum of Art

  Bags larger than a standard backpack need to be checked into coat check. Any backpack sizes or smaller can be worn on one shoulder.

• Smithsonian American Art Museum

  Backpacks may not be worn on the back, but must be carried on the side, under the arm, or on the front of the body.

There's a number of additional sources quoting this requirement:

• http://forums.childrenwithdiabetes.com/showthread.php?51224

  security people DID let me take it in as long as I kept it slung over ONLY ONE SHOULDER

• https://community.ricksteves.com/travel-forum/to-the-west/carrying-a-bag-or-purse-in-paris-museums

  I get the impression that things meant to be carried on one shoulder or in the hand are typically OK, while things that go over two shoulders are not.

Why is that? I first thought it's an easy way of implementing a size/weight limit. However, personal experience shows me that even when you are allowed to bring a backpack that is small enough to be carried on one shoulder, you have to wear it on one shoulder the all the time.

One possible reason is given here, but it's not very convincing to me:

Packs on the back are risks for the art. People turn around quickly and knock statues or scratch paintings with the packs when worn on two shoulders across the back.

Answer 1

Because if your bag is large enough to be only carried on your back (i.e. you cannot carry it on one shoulder), you'll much more likely to bump into, and do some damage to objects/sculptures/other people while turning around. This is because you don't see your bag, and it is much harder to estimate how big it is when maneuvering. It is much less likely when your bag is on your side, as you can see it.

Also with a large back on your back you're taking up to twice more space, which may be a problem near crowded exhibitions.

Update: Clément provided a link which confirmed the above theory, at least from Smithsonian Museum of American Art:

For the protection of our artworks, suitcases, large umbrellas, large bags, and large backpacks are not allowed in the galleries. Smaller backpacks and bags are permitted, at the discretion of the museum’s security officers, if they are hand-carried. Backpacks may not be worn on the back, but must be carried on the side, under the arm, or on the front of the body. These limitations help us protect the artworks from accidental damage.

Answer 2

People wearing backpacks sometimes forget it is there and inadvertently knock into/over things when they turn. I have not heard of the "one shoulder rule", but in the Smithsonian National Portrait Gallery I was asked to either hold my backpack or wear it backwards (on my front) while perusing the museum.

I've been whacked this way myself while waiting in line for a bus/airplane, and done the same to others, so accidentally swinging into things seems like a good possibility to me. In addition to people being more cognizant of a bag on one shoulder vs both, should they bump something with the bag, it is more free to move and will not hit with such force as with both straps.

Answer 3

While I like the optimism of George Y's answer, ultimately it relies on trusting the source to tell the truth.

However, as well as seeing this in US museums, we see this in US sports venues, where small handbags are allowed, but small backpacks are forbidden. In sports venues, bags are forbidden in order to prevent people from bringing in their own alcohol (and bombs). There are no artworks to protect in a sports stadium, so clearly there must be some other reason why handbags are allowed and backpacks aren't.

http://www.rosebowlstadium.com/visitor-center/code-of-conduct

Additionally, Australian museums do not draw a distinction between type of bag, but have a clause that covers all backpacks and bags, and is based on size.

Backpacks, umbrellas, and water bottles, and bags and packages larger than 30cm x 40cm, must be checked in.

https://www.mona.net.au/visit/facilities/

So no, the 'backpacks will destroy the art' hypothesis does not fit. Places that have no art have the same 'anti-backpack' policy, and places with lots of art to break will allow backpacks.

I suspect the answer is a much simpler one. Handbags are generally worn by adults, who pay and donate more to get into venues, and they often get jobs deciding on the bag policy to implement at venues. Backpacks are generally worn by children and teenagers, who make noise, damage things (whether they have a backpack or not), laugh at the willies on the statues/paintings, don't donate, don't vote, and don't get jobs as museum curators. Generally, they are considered a nuisance.

Ultimately, museums would like to ban all bags. They have made the decision that banning handbags would be more cost than benefit, so they permit them. This has painted them into a tight corner, and some are now allowing backpacks being worn like a handbag, because the only way to not allow it would be to admit the real reason handbags are allowed and backpacks aren't.

Australian sports and museums are both making separate pushes to try to attract younger people to their events, which may explain the lack of backpack bans down here.