What research method helped establish the maximum diving limit of 130 feet?

The method that helped establish the maximum diving limit of 130 feet is Doppler Ultrasound Research. This research utilizes advanced imaging techniques to study the effects of pressure and water on the human body at various depths. By observing how the body responds to increased pressure and the changes in gas bubbles within tissues, scientists gained crucial insights into the risks and physiological limits associated with deep diving. This understanding helped define safe diving practices and limits, including the recommended maximum of 130 feet.

The significance of this research lies in its ability to provide real-time data on how divers' bodies react under pressure, helping to prevent conditions such as decompression sickness. Through effective monitoring of blood flow and gas bubble dynamics, Doppler Ultrasound played a vital role in shaping safety standards for deep diving.