Agilent's Ultra High Matrix Introduction (UHMI) technology uses an innovative, computer-controlled, calibrated and reproducible “aerosol dilution” approach to extend the matrix tolerance of the Agilent 7900 ICP-MS to percent levels of dissolved solids – far beyond the normal limit for ICP-MS. UHMI uses an additional argon gas flow, added between the spray chamber and torch, to dilute the aerosol and so reduce both the sample matrix and the water vapor loading on the plasma. This allows the plasma to tolerate much higher Total Dissolved Solids (TDS) levels than the 0.2% that is typical for ICP-MS, and also reduces the effects of matrix suppression, allowing variable high matrix samples to be measured more accurately against simple aqueous standards. UHMI, available as an option for the 7900, is a sample dilution technique, but because it uses clean argon as the diluent it completely eliminates the problems of liquid dilution. Conventional liquid dilution (either manual or automated) has several potential disadvantages, including increased risk of sample contamination, leaks in tubing connections, dilution errors, waste disposal costs and sample prep time