1. API Gravity by Stereopycnometer 1Weigh clean, empty sample cell. 2Pour heated sample into cell unil ½ - ¾ full. 3Allow sample to cool to room temperature, then reweigh. 4Turn on power to stereopycnometer. 5Open cell vent and turn on flow. 6Open valve to helium so that pressure is about 20 psi. 7Allow instrument to purge for approximately 10 minutes. 8Turn off flow and insert sample cell into chamber (remove cylinder cover by turning counterclockwise). 9Replace chamber cover, turn on flow and purge for 10 minutes. 10Turn off flow. 11Zero digital display by turning black knob very slowly – allow time for stabilization then turn more if needed. 12Once reading is stabilized, turn selector valve to V A OUT. 13Close cell vent. 14Turn on flow. 15Allow pressure to reach about 17,000 on digital display then turn off flow. PPE Use Standard (SSP-0011) Y Full Face Shield / Goggles Hood Clothing—Chemical Protection Gloves—Chemical Personal Fall Protection Respirator / Filter Mask Supplied Air Job Hazards Y es Job Hazards Y es Access and EgressMoving Parts Activities of OthersNoise Adverse WeatherRail Movement Chemical ExposureSharp Edges ElectricitySlips, Trips, and Falls FatigueStatic Electricity Fire and ExplosionTrip Injuries Ground ContaminationTrapped Pressure Manual HandlingWorking at Height Other: References / Documents  N/A AreaUnitOperating Procedure #Certified byRevision #DatePage 3LabOPS-LB-NM-04706/28/111 of 2 API Gravity by Stereopycnometer Environmental  N/A Quality Assurance  N/A Special Instructions  Any problems, notify Shift Supervisor or Duane Chaisson. W A R N I N G C A U T I O N  Procedure Completed Date: Prepared By: Approved By:

2. AreaUnitOperating Procedure #Certified byRevision #DatePage 3LabOPS-LB-NM-04706/28/112 of 2 API Gravity by Stereopycnometer API Gravity by Stereopycnometer (continued) 16Record pressure reading as P 1. 17Turn selector valve to V A IN. 18Record pressure reading as P 2. 19Open cell vent. 20 To calculate result manually: 20.1 Determine sample weight by subtracting empty cell weight from weight of cell with sample. 20.2 Determine the true sample volume using the following equation: V S = V C + Va / [1 – (P 1 /P 2 )] where, V S = true sample volume V C & V A = constants determined from calibration of the instrument. 20.3 Determine the specific gravity of sample: Specific Gravity = wt. sample / V S 20.4 Determine APT Gravity as follows: API Gravity = (141.5 / Sp. Gravity) – 131.5 21 To calculate result using computer: 21.1 Click on desktop icon “Shortcut to Stereopynometer” to open spreadsheet. 21.2 Click menu icon in top left corner. 21.3 Click on “STEREOPYCNOMETER”. 21.4 Input data in missing fields (shaded gray). 21.5 Results will be automatically calculated by the software. 22Remove sample cell and place in oven. 23Replace chamber cover. 24Close cell vent. 25Turn off flow. 26Turn off helium. 27Turn off power to stereopycnometer. CAUTION: Oven mitts must be worn when removing sample cup from oven. Extreme care must be used as sample is hot! 28Once sample is pourable, discard into oily waste bucket in sink under hood. 29Clean sample cell using toluene.  Procedure Completed Date: Prepared By: Approved By: