Competitive horseback riding can be a dangerous sport, killing or maiming athletes. Some riders have begun wearing jackets that inflate when they are thrown off their mounts:

The two-pound vest is attached by a cord to a rider’s saddle and is worn over a traditional protective vest made of high-density foam. When a rider is thrown from a horse, the cord is yanked, puncturing a cartridge of carbon dioxide and inflating the vest. The vest can be reused after the cartridge is replaced. Point Two said its vest inflates in one-tenth of a second; Hit Air said its average rate is one-quarter of a second.

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