Any iron(III) ions present in the water sample are reduced to iron(II) ions by ascorbic acid before the complex is formed. This method complies with regulations in many countries and therefore can often be used for reporting purposes. Contact your local Hach distributor to determine if this method can be used for regulatory reporting purposes in your country. SHELF LIFE OF TEST REAGENT The test reagents are stable at room temperature for 30 months as indicated by the expiration date on the packa

Printed in the U.S.A. eac 07/03 4ed Visit http: //Table of Contents Safety Precautions.................................................................................................................................................... 7 Specifications............................................................................................................................................................ 9 Section 1 Introduction ...................................................................