This calculator is valid subject to the following conditions:
- Temperature must be between -180°C and -140°C inclusively
- The average molecular weight is no more than 20.0 kg/kmol
- No more than 5% molar of nitrogen
- No more than 5% of n-Butane and i-Butane combined
- No more than 1% of pentanes, heavier hydrocarbons and oxygen
- ISO 6578 (1991) Refrigerated hydrocarbon liquids - Static measurement - Calculation procedure