Scope1.1 This procedure covers the determination of diethanolamine, triethanolamine, N-methyldiethanolamine and N-ethyldiethanolamine (referred to collectively as ethanolamines in this test method) in surface water by direct injection using liquid chromatography (LC) and detected with tandem mass spectrometry (MS/MS). These analytes are qualitatively and quantitatively determined by this test method. This test method adheres to single reaction monitoring (SRM) mass spectrometry.1.2 This test method has been developed by US EPA Region 5 Chicago Regional Laboratory (CRL).1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 The Detection Verification Level (DVL) and Reporting Range for the ethanolamines are listed in Table 1.1.4.1 The DVL is required to be at a concentration at least 3 times below the Reporting Limit (RL) and have a signal/noise ratio greater than 3:1. Fig. 1 displays the signal/noise ratios at the DVLs and at higher concentrations for N-methyldiethanolamine.