American Society for Testing and Materials (ASTM) D721-06, is the method for testing the oil in paraffin wax .  

The technique is slow (the process takes about 2 hours) and requires technical skills and the use of hazardous solvents. The Oil in Wax NMR method is a ratio method so the sample does not need to be weighed. Generally , the Oil in Wax NMR method can exploit two different hardware configurations to optimize for two ranges of oil content dependent on the sample and/or user requirements:

• 2% and above: rapid measurement using a standard with 10-mm diameter samples and sample pre-conditioning at low temperature (usually;5 °C).
• 0.1% to 2% oil: low detection limit measurement using an with 10-mm diameter samples and equipped with a low-maintenance , fluid-cooled temperature-regulated probe (usually ;5 °C or less). sales3 at paraffinco dot com.