The Thermo Scientific iCE 3000 Series Atomic Absorption Spectrometers fitted with Zeeman Graphite Furnace and Graphite Furnace Autosamplers are entirely suitable for the determination of arsenic concentrations in natural water samples using the EPA 200.9 methodology. The Method Development Tools provided, particularly the Graphite Furnace TeleVision accessory and the automatic Ash Atomize wizard, allow the instrument parameters to be quickly and reliably optimized.