Dive Theory - Simple Explanations of the Physics and Physiology of Scuba Diving
Dive Theory Essentials
A brief overview of theory topics that all scuba divers should be familiar with.
Ear Equalization Basics
How do scuba divers equalize their ear pressure to avoid ear pain when diving? Learn about the Valsalva maneuver and other ear equalization techniques, as well as how to deal with common equalization problems.
Buoyancy Basics for Scuba Diving
An understanding of buoyancy is key to safe and easy scuba diving. While the concept of buoyancy may be confusing at first, it becomes clearer...
Archimedes Principle - Essential Concepts for Scuba Diving
Archimedes' Principle states that an object's buoyancy is equal to the weight of the water that it displaces. Why is Archimede's Principle important for scuba diving?
Buoyancy in Salt Water vs Fresh Water
Scuba diving concepts: How does an object's buoyancy change from fresh water to salt water? An object is more buoyant in freshwater vs saltwater because . . .
How Does Pressure Effect Scuba Divers?
Water pressure increases with depth. Water pressure effects almost all aspects of scuba diving, include equalization, buoyancy, bottom times, and the risk of decompression sickness (DCS). Review basic dive theory regarding depth and pressure in scuba diving.
Air Consumption Rates for Scuba Diving - SAC Rates, RMV Rates, Easy Calculations
What is your air consumption rate? Learn about air consumption rates, how to calculate them, and how to use them to plan a dive.
Every Dive Is a Decompression Dive
Every scuba dive is a decompression dive because every dive involves the compression and decompression of nitrogen in a diver's body. Shifting the way in which divers commonly view recreational diving may lead to more conservative diving practices and a greater emphasis on following safety guidelines.
The Sponge Analogy - Understanding Nitrogen Absorption
Does the concept of nitrogen absorption confuse you? The sponge analogy is an simple tool to help scuba divers understand how their bodies absorb and off-gas nitrogen when diving.
The Greatest Pressure Change Is Near the Surface
Some divers do not realize that they closer they are to the surface, the more rapidly the pressure changes. This basic concept, but often over-looked, concept is essential for safe scuba diving.
Boyle's Law and Scuba Diving
Boyle's Law, PV=c, is useful in scuba diving because Boyle's Law helps scuba divers predict how air will expand and compress with water pressure. Read an explanation of Boyle's Law and how it applies to scuba diving.
Scuba Diving Pranks - What Is Prank You Have Pulled on a Fellow Scuba Diver
What Is the best prank that you have pulled on a fellow scuba diver? Read about other scuba diver's pranks and share your own here.
Residual Nitrogen Time (RNT) and Scuba Diving
What is residual nitrogen time in scuba diving? This explanation will help divers to understand what residual nitrogen time represents and how to use this number in recreational diving when calculating repetitive dive parameters.
Surface Intervals (SI) and Scuba Diving
What is a surface interval (SI) in scuba diving? A surface interval is the time a diver spends above water in between two dives. To stay safe and comfortable, a diver should
Adjusting Trim Using Equipment Choice and Configuration - Scuba Diving Tips
Adjust and select scuba diving gear to achieve proper trim (horizontal position in the water) using these seven tips. A diver's trim is affected by his weight distribution, wetsuit, fins, regulators, tank position and more.
Sound Travels About 4 Times Faster in Water Than in Air
Does light or sound travel through water faster? Sound travels through water about 4 times faster than in air. Read-in depth answers to this and other PADI Open Water Course Knowledge Review Questions here.
Pressure Groups and Scuba Diving
What is a pressure group in scuba diving? A pressure group is an alphabetical representation of the amount of nitrogen a diver has absorbed after diving or after a surface interval. For safe diving, a diver should