**Particle Settling Rate
Determination**

To use the spreadsheet below, follow the following instructions every time you want to check a settling velocity.

Enter in the properties of the particle and the fluid in which the particle is moving (normally air). The cells colored in green.

Then enter the particle diameter. The cell colored blue.

Then check the Reynolds number. The yellow cell.

If the Reynolds number is less than 0.1 then use the top purple settling velocity value.

- If the Reynolds number is between 0.1 and 1000 then use the middle purple settling velocity value
- If the Reynolds number is between 1000 and 350 000 then use the bottom purple settling velocity value.

These values should only be used as a guide.