User manual HANNA INSTRUMENTS HI 93754C-25 HR

[. . . ] Oxidizable organic compounds reduce the dichromate (orange) ion to the chromic (green) ion. HI 93754A-25 LR HI 93754B -25 MR HI 93754C-25 HR 10 - Leave the vials in the tube rack to cool to room temperature. Do not shake or invert them anymore otherwise the samples may become turbid. 11 - For colorimetric determination of COD, follow the procedure described in the Photometer Instruction Manual*. [. . . ] 3 - Remove the cap from a reagent vial for the required COD range. Note: the reagent is light sensitive, thus store the unused vials in their container and in a refrigerator if possible. 4 - Use the supplied syringe and add 2 ml (for LR and MR test) or 0. 2 ml (for HR test) of sample to the vial, while keeping the vial at a 45-degree angle. Range 0-150 mg/L 0-1500 mg/L 0-15000 mg/L Reagent Vial cap code color HI 93754A-25 red HI 93754B-25 white HI 93754C-25 green Sample q. ty 2. 0 mL 2. 0 mL 0. 2 mL www. hannainst. com Dear Customer, Thank you for choosing a Hanna product. Please read this instruction manual carefully before using the reagent. This manual will provide you with the necessary information for the correct use of the reagents. If you need additional information, do not hesitate to mail us at tech@hannainst. com. Note: to measure exactly 0. 2 mL of sample with the syringe, push the plunger completely into the syringe and insert the tip into sample. Pull the plunger out until the lower edge of the seal is on the 0. 0 mL mark of the syringe. Insert the syringe into the vial and push the sample out until the lower edge of the seal is on the 0. 2 mL mark. 5 - Replace the cap tightly and mix by inverting the vial a couple of times. Warning: as the vial becomes very hot during mixing, be careful in handling it. 6 - Using the other clean syringe, add to another reagent vial deionized water repeating steps 4 and 5 (2 ml for LR and MR, and 0. 2 ml for HR). Note: for an accurate measurement, run a blank with each set of samples and use the same box of reagents for blank and samples. 7 - Insert the vials into the reactor* and heat them for 2 hours at 150°C. HEALTH & SAFETY SSAFETY The chemicals contained in these kits may be hazardous if improperly handled. Read the Health & Safety Data Sheet before performing tests. Safety equipment: Wear suitable eye protection and clothing, and follow instructions carefully. [. . . ] ·HI 93754C-25 HR: COD High Range (0 to 15000 mg/L) Vial cap color: GREEN. 8 - At the end of the digestion period, turn the reactor off (if you are using the Hanna Reactor, it will automatically switch off). Wait for twenty minutes to allow the vials to cool to about 120°C. 9 - Invert each vial several times while still warm, then place them in the HI 740216 rack. [. . . ]