For an inflatable life jacket to inflate automatically, which mechanism may it use?

An inflatable life jacket typically uses a water-activated mechanism to inflate automatically when it comes into contact with water. This system relies on a sensor that detects the presence of water and triggers the inflation process, ensuring that the life jacket provides immediate buoyancy in an emergency situation.

Using a water-activated mechanism is crucial for safety, as it enables the life jacket to deploy without requiring the wearer to take any manual action, which is particularly important in situations where a person may be incapacitated or unable to pull a cord. This feature enhances the reliability and effectiveness of the life jacket in saving lives during boating accidents.

The other mechanisms mentioned, such as a timer-based mechanism or a temperature-activated mechanism, are not standard for inflatable life jackets because they would not guarantee timely inflation in an emergency. Similarly, a manual pull cord requires the user to take specific action, which may not always be possible in a crisis. Thus, the water-activated mechanism is the most effective and widely used method for automatic inflation in inflatable life jackets.