Are there any self-inflating life jackets on board? What are they used for?

A self-inflating life jacket is a life jacket that inflates automatically as soon as it is submerged. The dissolution of a salt tablet triggers a pressurized CO2 cartridge. As the gas is released, it inflates the vest’s bladder. The advantage of this system is that the vest is very compact and does not restrict movement when worn. Here is a demonstration.

Some rental companies provide self-inflating life jackets, but not all of them. In fact, every time the life jacket is inflated (whether someone jumps into the water with it—for fun or otherwise—or if it gets wet, for example by being left at the bottom of a dinghy with a little water), the charter company must replace the cartridge and salt tablet at the end of the charter period, which costs around forty USD and takes time.