Density of the gas (kg/Nm³): This is crucial because the density varies with the type of gas. Standard density values for some common gases are:
Air: 1.225 kg/Nm³ (at 0°C and 1 atm)
Oxygen: 1.429 kg/Nm³
Nitrogen: 1.2506 kg/Nm³
Methane (Natural Gas): 0.717 kg/Nm³
CO₂: 1.977 kg/Nm³
Temperature and Pressure Conditions: The density of a gas varies with temperature and pressure. The standard condition is often defined as 0°C (273.15K) and 1 atm pressure (101.325 kPa), known as "Normal" conditions (Nm³).