Equivalent Air Depth (EAD) Calculator

Formula

To calculate the Equivalent Air Depth (EAD):

\[ EAD = \left( \frac{(D + 33) \times FN}{0.79} \right) - 33 \]

Where:

\(EAD\) is the Equivalent Air Depth (feet)
\(D\) is the Total Depth (feet)
\(FN\) is the Fraction of Nitrogen

What is Equivalent Air Depth?

Equivalent Air Depth (EAD) is a concept used in diving to express the depth at which a diver breathes air that has the same partial pressure of nitrogen as a given gas mixture. This calculation is important for divers to understand their exposure to nitrogen and manage their decompression schedules appropriately.

Example Calculation 1

Let's assume the following values:

Total Depth (\(D\)) = 100 feet
Fraction of Nitrogen (\(FN\)) = 0.78

Using the formula:

\[ EAD = \left( \frac{(100 + 33) \times 0.78}{0.79} \right) - 33 = 110.61 \text{ feet} \]

The Equivalent Air Depth is 110.61 feet.

Example Calculation 2

Let's assume the following values:

Total Depth (\(D\)) = 60 feet
Fraction of Nitrogen (\(FN\)) = 0.75

Using the formula:

\[ EAD = \left( \frac{(60 + 33) \times 0.75}{0.79} \right) - 33 = 75.51 \text{ feet} \]

The Equivalent Air Depth is 75.51 feet.