Hach DR2400 - Page 115

Boron
Boron
Boron_PP_Other_CAR_Eng_Ody.fm Page 3 of 4
The BoroVer 3/Sulfuric Acid Solution is highly acidic. Neutralize to pH 6–9
and flush down the drain for disposal. For more information on waste
management, see Section 4.
Accuracy Check
Standard Additions Method (Sample Spike)
1. After reading test results, leave the unspiked sample in the instrument.
Verify the chemical form.
2. Touch
Options. Touch Standard Additions. A summary of the standard
additions procedure will appear.
3. Touch
OK to accept the default values for standard concentration, sample
volume, and spike volumes. Touch
Edit to change these values. After values
are accepted, the unspiked sample reading will appear in the top row. See
Standard Additions in the instrument manual for more information.
4. Snap the neck off a Boron Voluette
®
Ampule Standard, 250-mg/L B.
5. Prepare three sample spikes. Fill three mixing cylinders (Cat. No. 1896-40)
with 25 mL of sample. Use the TenSette
®
Pipet to add 0.1 mL, 0.2 mL, and
0.3 mL of standard, respectively, to each sample and mix thoroughly.
6. Analyze 2.0 mL of each sample spike as described in the procedure above,
starting with the 0.1 mL sample spike. Accept each standard additions
reading by touching
Read. Each addition should reflect approximately 100%
recovery.
7. After completing the sequence, touch
Graph to view the best-fit line through
the standard additions data points, accounting for matrix interferences. Touch
View: Fit, then select Ideal Line and touch OK to view the relationship between
the sample spikes and the “Ideal Line” of 100% recovery.
See Section 3.2.2 Standard Additions on page 32 for more information.
Standard Solution Method
Check the accuracy of the test using Boron Standard Solution, 10-mg/L as B.
Prepare this solution as follows:
1. Using Class A glassware, pipet 10.00 mL of the Boron Voluette Ampule
Standard, 250-mg/L B, into a 250-mL volumetric flask. Dilute to volume
with deionized water. Swirl to mix.
2. To adjust the calibration curve using the reading obtained with the
10.0-mg/L standard solution, touch
Options on the current program menu.
Touch
Standard Adjust: Off.
3. Touch
On. Touch Adjust to accept the displayed concentration (the value
depends on the selected chemical form). If an alternate concentration is used,
touch the number in the box to enter the actual concentration, then touch
OK.
Touch
Adjust.
See Section 3.2.4 Adjusting the Standard Curve on page 40 for more information.