Final answer:
The requirement for all personal flotation devices is that they must be Coast Guard approved, not necessarily worn all the time, brightly colored, or made of waterproof material. Buoyancy advantage rules for high-tech swimsuits can be verified through testing by swimming federations.
Step-by-step explanation:
The requirement for all personal flotation devices (PFDs) is that they must be Coast Guard approved. This approval ensures that the PFD meets strict guidelines for safety and performance. While wearing PFDs at all times, having them brightly colored, and making them of waterproof material are good safety practices, they are not mandatory requirements. Coast Guard approval means that the PFD has been tested for factors such as buoyancy and structural integrity, among other criteria.
Regarding the rule that high-tech body swimsuits, such as those introduced in 2008 for the Beijing Olympics, should not provide any buoyancy advantage, this can be verified through rigorous testing. The swimsuits would be examined and tested to measure their buoyancy in water and to ensure they do not aid in making the swimmer more buoyant. This testing would be done by swimming federations or other designated bodies to ensure the swimsuits conform to international standards.