Specifications
2
Rinsing, Cleaning, and Storage Procedures
Note: See Cleaning Materials below for discussion of appropriate
sources / concentrations of water, Triton X-100, bleach, and tubing.
CAUTIONS:
The conductivity cell is primarily glass, and can break if
mishandled. Use the correct size Tygon tubing; using tubing with a smaller ID will make it difficult to remove the
tubing, and the cell end may break if excessive force is used. The correct size tubing for use in cleaning / storing
all conductivity cells produced since 1980 is 7/16" ID, 9/16" OD. Instruments shipped prior to 1980 had smaller
retaining ridges at the ends of the cell, and 3/8" ID tubing is required for these older instruments.
Do not put a brush or object (e.g., Q-Tip) inside the conductivity cell to clean it or dry it. Touching and
bending the electrodes can change the calibration; large bends and movement of the electrodes can damage the
cell.
If an SBE 43 dissolved oxygen (DO) sensor is plumbed to the CTD - Before soaking the conductivity cell for
more than 1 minute in Triton X-100 solution, disconnect the tubing between the conductivity cell and DO
sensor to prevent extended Triton contact with the DO sensor membrane (extended Triton contact can damage the
membrane). See Application Note 64 for rinsing, cleaning, and storage recommendations for the SBE 43.
Active Use (after each cast)
1. Rinse: Remove the plumbing (Tygon tubing) from the exhaust end of the conductivity cell. Flush the cell with a
0.1% Triton X-100 solution. Rinse thoroughly with fresh, clean water and drain.
If not rinsed between uses, salt crystals may form on the conductivity cell platinized electrode surfaces. When
the instrument is used next, sensor accuracy may be temporarily affected until these crystals dissolve.
2. Store: The intent of these storage recommendations is to keep contamination from aerosols and spray/wash on the
ship deck from harming the sensors calibration.
No danger of freezing: Fill the cell with a 500 1000 ppm bleach solution, using a length of Tygon tubing
attached to each end of the conductivity sensor to close the cell ends.
Danger of freezing: Remove larger droplets of water by blowing through the cell. Do not use compressed
air, which typically contains oil vapor. Attach a length of Tygon tubing to each end of the conductivity cell to
close the cell ends.
Routine Cleaning (no visible deposits or marine growths on sensor)
1. Agitate a 500 1000 ppm Bleach solution warmed to 40 C through the cell in a washing action (this can be
accomplished with Tygon tubing and a syringe kit see Application Note 34) for 2 minutes. Drain and flush
with warm (not hot) fresh, clean water for 5 minutes.
2. Agitate a 1%-2% Triton X-100 solution warmed to 40 C through the cell many times in a washing action
(this can be accomplished with Tygon tubing and a syringe kit). Fill the cell with the solution and let it soak for
1 hour. Drain and flush with warm (not hot) fresh, clean water for 5 minutes.
Cleaning Severely Fouled Sensors (visible deposits or marine growths on sensor)
Repeat the Routine Cleaning procedure up to 5 times.
Long-Term Storage (after field use)
1. Rinse: Remove the plumbing (Tygon tubing) from the exhaust end of the conductivity cell. Flush the cell with a
0.1% Triton X-100 solution. Rinse thoroughly with fresh, clean water and drain. Remove larger droplets of
water by blowing through the cell. Do not use compressed air, which typically contains oil vapor.
2. Store: Attach a length of Tygon tubing to each end of the conductivity cell to close the cell ends. The loop prevents
any contaminants from entering the cell.
Storing the cell dry prevents the growth of any bio-organisms, thus preserving the calibration.
3. When ready to deploy again: Fill the cell with a 0.1% Triton X-100 solution for 1 hour before deployment. Drain
the Triton X-100 solution; there is no need to rinse the cell.
Soaker tube
SBE 4 Conductivity Sensor