Calibration of Intermediate and Large Volume Standards Gravimetric Method Using an Equal Arm Balance

1 Page 1 11/15/2006 SOP 15 Page 1 of 8 SOP No. 15 Recommended Standard Operations Procedure for Calibration of Intermediate and Large Volume Standards Gravimetric Method 1 Using an Equal-Arm Balance 2 1 Introduction 1.1 Purpose o... Open at page → 2 Page 2 11/15/2006 SOP 15 Page 2 of 8 Table 1. Laboratory environmental conditions Procedure Temperature Relative Humidity Gravimetric 20 °C to 23 °C, a set point ± 2 °C, maximum change 1 °C/h 40 % to 60 % ± 10 % max change / 4... Open at page → 3 Page 3 11/15/2006 SOP 15 Page 3 of 8 2.3.4 Calibrated thermometer accurate to ± 0.5 °C with recent calibration values that are traceable to NIST to determine air temperature. 2.3.5 Calibrated barometer accurate to ±135 Pa (1 mm... Open at page → 4 Page 4 11/15/2006 SOP 15 Page 4 of 8 2.3.3.1 Fill the vessel with pure water to the zero point on the neck scale. Be sure the vessel is level. Bounce the liquid to disturb the meniscus to assure it has reached equilibrium level... Open at page → 5 Page 5 11/15/2006 SOP 15 Page 5 of 8 3 Calculations 3.1 To calculate the filled, empty, or drained mass, use the following equation from SOP 4 using Option A. Table 2. Variables for Equation 2 Symbol Description S standard refe... Open at page → 6 Page 6 11/15/2006 SOP 15 Page 6 of 8 3.5 To convert the volume measured in mL (cm 3) to gal: V gal = (0.000 264 172) V mL (There are 3 785.411 784 mL per gal.) Table 2. Variables for volume equation Symbol Description ρw densit... Open at page → 7 Page 7 11/15/2006 SOP 15 Page 7 of 8 5 Assignment of Uncertainties The limits of expanded uncertainty, U, include estimates of the standard uncertainty of the mass standards used, u s, plus the uncertainty of measurement, sp, a... Open at page → 8 Page 8 11/15/2006 SOP 15 Page 8 of 8 Appendix Test Notes 1 Pour and drain times. It is impractical to completely drain a filled container, because some of the contents will remain as a film. By strict adherence to a specified p... Open at page →