Enter the volume flow rate (ml/s) and the maximum velocity (cm/s) into the ERO Calculator. The calculator will evaluate the ERO.

## ERO Formula

The following two example problems outline the steps and information needed to calculate the ERO.

ERO = VFR / Vm

Variables:

- ERO is the ERO (cm^2)
- VFR is the volume flow rate (ml/s)
- Vm is the maximum velocity (cm/s)

To calculate the ERO, divide the volume flow rate by the maximum velocity.

## How to Calculate ERO?

The following steps outline how to calculate the ERO.

- First, determine the volume flow rate (ml/s).
- Next, determine the maximum velocity (cm/s).
- Next, gather the formula from above = ERO = VFR / Vm.
- Finally, calculate the ERO.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

volume flow rate (ml/s) = 30

maximum velocity (cm/s) = 20

ERO = VFR / Vm** **= ?