In cities where tourists often use bike-sharing services helmet use by customers is uncommon. Riders either have to ride helmetless or buy their own helmet. This problem has been met with a design for a foldable paper bike helmet.
This helmet is inexpensive and small so it can be bought at a bike-sharing service and is disposable so riders do not have to keep the helmet when they will only be using it for a short period of time. Foldable helmets could be sold in vending machines for convenience where a traditional helmet would be too large to fit.