Hach 2100P ISO Manual page 23

SECTION 2,
•
Do not return standard from the sample cell back into the its
original container. Standard contamination will result.
•
Store standards between 0 and 25 °C.
•
For long-term storage, refrigeration at 5 °C is recommended. Do
not store above 25 °C.
•
Allow the standard to acclimate to ambient instrument conditions
before use (not to exceed 40 °C).
•
Store away from direct sunlight. Store vials in their respective kit or
shipping box with the cover in place.
2.4.1.2 Preparing Bulk StablCal Stabilized Standards
Bulk standards that have been sitting undisturbed for longer than a
month must be shaken to break the condensed suspension. Start at
step 1 for these standards. If the standards are used on at least a weekly
interval, start at step 3.
When using <0.1-FNU StablCal Standards, do not shake or invert.
1. Shake the standard vigorously for 2–3 minutes to suspend particles.
2. Allow the standard to stand undisturbed for 5 minutes.
3. Gently invert the bottle of StablCal 5 to 7 times.
4. Prepare the sample cell for measurement using traditional
preparation techniques. This usually consists of oiling the sample
cell (see Section
the same orientation in the sample cell compartment
(see Section 3.2.2 on page
variations in the sample cell.
5. Rinse the sample cell at least once with the standard and discard
the rinse.
6. Immediately fill the sample cell with the standard. Cap the sample
cell and let it stand for one minute. The standard is now ready for
use in the calibration procedure,
continued
3.1.1 on page
39). This step will eliminate any optical
35) and marking the cell to maintain
Section 2.4.3 on page
23
27.