US4 units are used for gas flow runs. The Units column shows the measurement units. The RealFLO Display column shows how these units are displayed on the screen and in printed reports.
| Parameters and Values | Units | RealFLO Display |
| Pipe and Orifice Diameters | inches | inches |
| Static, Base and Atmospheric Pressure | psi | psi |
| Differential Pressure | inches H2O at 60 °F | in H2O at 60F |
| Flowing and Base Temperature | °F | F |
| Viscosity | centipoise | cP |
| Density | lbm/ft3 | lbm/ft3 |
| Mass | lbm | lbm |
| Mass Flow Rate | lbm/hr | lbm/hr |
| Volume | MCF | MCF |
| Volume Flow Rate | MCF/hr | MCF/hr |
| Heating Value | BTU(60)/ft3 | BTU/ft3 |
| Energy | MBTU(60) | MBTU |
| Energy Flow Rate | MBTU(60)/hr | MBTU/hr |
| Flow Extension (Method 1) | kg/m2s | kg/m2s |
| Turbine Rate (volume) | pulses/ft3 | pulses/ft3 |
| Turbine Rate (mass) | pulses/lb | pulses/lb |
| Altitude | feet | feet |
The prefix M above units stands for thousands. The prefix MM above units stands for millions.
- MCF is thousands of cubic feet (103 ft3).
- MMCF is millions of cubic feet (106ft3).
- MBTU is thousands of BTU (103 BTU).
- MMBTU is millions of BTU (106 BTU).
- M in metric and SI unit sets stands for millions (106 ).
NOTE: Be aware that 'M' in Metric and SI units represents a different quanitiy to that stated above.