**About Gas Piping Size Calculator (Formula)**

The Gas Piping Size Calculator determines the required pipe diameter for a given volumetric flow rate of gas. The formula used is:

**q = 3,550 * [d^5 / (1+3.6/d + .03 d)]^1/2 * (h / (LSG))^1/2**

**where:**

- q is the volumetric flow rate in cubic feet per hour (cfh)
- d is the diameter of the pipe in inches
- h is the pressure drop
- L is the length of the pipe in feet
- SG is the specific gravity of the gas (typically 0.60 for natural gas)

This formula takes into account the effects of pressure drop and the gas properties on the flow rate, and provides a reliable estimate for the required pipe diameter. The Gas Piping Size Calculator is useful for engineers and designers in the gas industry to ensure safe and efficient gas distribution.