Geodesic Sensor Net - Preparing the Electrolyte Formulation

6: Applying the GSN
58
Geodesic Sensor Net Technical Manual S-MAN-200-GSNR-001 • January 31, 2007
Caution!: Consider not accepting subjects who use nonpermanent hair dye, which
can also stain the GSN. Though the staining has no effect on performance, it can
have a dramatic impact on Net appearance.
Before your subject arrives, make the following preparations.
• Prepare a fresh batch of electrolyte formulation (for step-by-step instructions,
see “Preparing the Electrolyte Formulation” on page 58).
• Have available a measuring tape, pipettes, syringes, china markers, and three
clean towels (each approximately 40 x 60 centimeters). EGI offers a Net Support
Kit (see Chapter 12, "Accessories and Supplies”) that contains these items.
• Have Nets on hand in a variety of sizes to ensure that you have one that fits the
subject. Be sure that each Net has undergone a disinfecting, rinsing, and drying
regime as described in Chapter 7, "Rinsing and Disinfecting.”
WARNING!:
Never apply a Net that has not been properly cleaned, disinfected,
and rinsed.
Note: It is ideal but not necessary for the Net to be dry before using it on another subject.
If you do use a Net that is not dry, be sure to squeeze each sponge as it soaks in the
electrolyte, to facilitate intake.
Preparing the Electrolyte Formulation
For the electrolyte formulations, use only the designated “electrolyte formulation”
plastic bucket from the Net Support Kit.
WARNING!:
Do not reuse electrolyte formulations between subjects or sessions.
Dispose of them according to your institution’s guidelines.
EGI offers two electrolyte formulations:
•
HydroCel Saline (with sponge insert) : For standard (2-hour) recordings, this is
the classic potassium chloride saline and surfactant solution used for rapid
application. The HydroCel Saline comes in powder form and must be mixed
with water before using. No subject cleanup is required.