Think You Have It Figured Out? 

Follow  This  Printable  "Techie  Check  List"  To  Make 
Sure  That  Your  Spec    Session  Goes  Smoothly

Follow the specific directions STEP by STEP for the parameter you are measuring in the Hach Manual

Remember the Blank is just the sample with no chemicals added to it.

Be sure to insert the cell holder before reading the sample.

Close the light shield before attempting to take readings.

Throw away empty reagent packets.

Remove the cell holder and the light shield before turning off the spectrometer.

Put away all materials and clean up the work area.

Rinse out sample vials, dry them with paper towels, and let them on the shelf to dry.

Put all plastic bottles in the dish washer (along with their tops), and wash your hands thoroughly.