US Patent 10351251 Audio evacuation system readiness indicator

An inflatable flotation device includes an inflatable body configured to be stored in a deflated state and to be inflated in response to an event. The inflatable flotation device also includes a switch attached to the inflatable body and configured to switch from an off state to an on state in response to the inflatable body being inflated at least one of to or beyond a predetermined inflation level. The inflatable flotation device also includes a speaker attached to the inflatable body, electrically coupled to the switch, and configured to generate an audio signal indicating that the inflatable body is ready for use in response to the switch being switched from the off state to the on state.