Hach DR2400 - Page 361

DR/2400
Lead
Lead_UniCell_Other_PAR_Eng_Ody.fm Page 1 of 4
• Adjust pH of preserved samples to between pH 3–5 before analysis.
• Digest water samples with a pH higher than 9 before analysis.
• Clean the outside of the vial before placing it in the instrument. Wipe with a damp towel, followed by a dry one.
• Use the standard solution or standard addition method to verify results. See Accuracy Check.
• See Section 3.2.4 in the procedure manual for information on adjusting the calibration curve.
• Make sure that the temperature of the sample and the reagents is between 15–25 °C.
• Underrange appears on the display when the instrument is zeroed or when the determined sample concentration is below the
operating range listed for this method.
Lead
PAR Method
UniCell™ Vials
(0.20 to 2.00 mg/L)
Scope and Application: For wastewater process control
1. Touch Hach
Programs.
Select program
286 Lead, HCT 152.
Touch
Start.
2. Pipet 10.0 mL of
sample into the reaction
tube (red cap).
3. Use the spoon to add
one level spoonful of
Masking Agent A
(HCT 152 A) to the
reaction tube.
4. Close the reaction
tube and invert several
times to mix.
5. Touch the timer icon.
Touch
OK.
A two-minute reaction
period will begin.
6. Pipet 1.5 mL of Buffer
Solution B (HCT 152 B)
into a sample vial
(light red cap).
7. Pipet 4.0 mL of
sample from the reaction
tube into the sample vial.
8. Close the sample vial
and invert several times
to mix.
Tips and Techniques
UniCell Vials
Hach Programs