YOKOGAWA TB820D, User Manual, Page: 54 / 87

< 7. Calibration >
7-5
IM 12E01B30-02EN 2nd Edition : June 09 , 2021-00
<How to clean the check tool>
Clean the dust and dirt on the surface of the check tool.
(1) Cleaning with the attached silicone cloth or washing
If the surface is dusty, use the included silicone cloth to gently wipe it off and remove the
dust. At this time, do not rub hard the surface.
If the dust and dirt cannot be removed by just wiping it, wash it with tap water.
After cleaning, drain the water well and absorb the remaining water with tissue paper. At this
time, do not rub the surface.
(2) Cleaning with detergent
Touch the surface with your hands. If your hands still get dirty, or if the stain does not come
off even after cleaning (1), clean it with the included detergent or neutral detergent.
Take the following steps below for cleaning.
a. Dissolve an appropriate amount of detergent in tap water and soak the check tool.
b. Shake the check tool in the detergent solution to clean the surface.
c. If the stain is tough and does not come off by just shaking it, rub gently the surface in the
detergent solution.
d. After the stain comes off, rinse off the washing solution with the tap water and drain the
water droplets on the surface.
e. Wipe off the residual solution on the surface with tissue paper, but do not rub hard the
surface.
CAUTION
• Avoid rubbing hardly regardless of the material of the cloth.
• Do not use agents other than mild detergent for wash; avoid ethanol, acetone, and other
solvents.
• Do not use fingers to wash off the stain on the surface.
• Handle with care. Scratches on the surface may interfere with accurate measurement.
n
Formazin Standard Solution
WARNING
• The reagents are harmful if inhaled or swallowed.
• In case of contact with skin, flush skin with plenty of soap and water. Seek medical advice,
as appropriate, if symptoms appear.
• A Class A extinguisher should be provided in work area.
• Wear protective goggles, lab coat, and protective gloves to prevent skin contact. Use a vent
hood in the indoor workplace.
• For details of the chemical handling, refer to the Material Safety Data Sheets (MSDS).
A turbidity standard calibration solution should be prepared by diluting a 400 NTU formazin
standard stock solution. This section describes the procedures for preparing a standard stock
solution and a diluted solution for calibration.