Enter the atmospheric or vent pressure (Pa) and the absolute pressure used for the purge (Pa) into the Gas Purge Calculator. The calculator will evaluate the Gas Purge.

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## Gas Purge Formula

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

GP = -4/log(Pa/Ph)

Variables:

- GP is the Gas Purge (number of purge cycles)
- Pa is the atmospheric or vent pressure (Pa)
- Ph is the absolute pressure used for the purge (Pa)

To calculate the gas purge rate, divide negative 4 by the log of the ratio of the atmospheric vent pressure by the purge pressure.

## How to Calculate Gas Purge?

The following steps outline how to calculate the Gas Purge.

- First, determine the atmospheric or vent pressure (Pa).
- Next, determine the absolute pressure used for the purge (Pa).
- Next, gather the formula from above = GP = -4/log10(Pa/Ph).
- Finally, calculate the Gas Purge.
- 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.

atmospheric or vent pressure (Pa) = 30

absolute pressure used for the purge (Pa) = 20

GP = -4/log10(Pa/Ph)** **= ?