For most biopotential recordings, it is important to provide a low impedance contact with the tissue underneath the skin at the electrode site. Consequently skin should be abraded with pumice, an ELPAD or ELPREP. Alcohol prep pads are generally not preferred because they dry the skin. The purpose of abrasion is to remove dead cells from the outer layer of skin. These cells form an electrical barrier. Electrical communication from the electrode surface to the underlying tissue is most often through a water-based gel. For good recordings, this gel must soak into the skin. As alcohol dries out the skin, it slows the process of establishing the liquid bridge between electrode and tissue.
One exception where abrasion is not recommended is measurement of electrodermal activity (skin conductance). Here skin should be rinsed but neither washed with soap nor abraded. As the conductivity of the skin at the electrode site is the variable to be measured in this case, no steps should be taken to modify that conductance artificially.
BSL Home enables students to safely conduct hands-on physiology labs wherever they are! Purchase this complete lab solution to preserve practical lab experience! Includes MP41 Unit+Lead Set with BSL Home software, EL503 electrodes, WRAP1 self-adhering wrap for EEG lessons, and disposable 9 V battery. For instructors—BSL Home makes it easy for instructors to continue running practical […]
Comparing Diaphragm Tissue Between Healthy and Ill Patients The human diaphragm is one of the primary muscles used in respiration, contracting and expanding to control breathing. To measure how much diaphragms move for critically ill patients (in an Intensive Care Unit) compared to diaphragms in a healthy subject, patients at “Papageorgiou” General Hospital in Thessaloniki, […]
BIOPAC’s ventilator testing equipment and expertise supports STARK Industries’ effort to manufacture, validate, and test NASA JPL’s VITAL Ventilators Goleta, California – June 16, 2020 BIOPAC Systems, Inc. announced a partnership with STARK Industries, LLC to provide ventilator validation and testing equipment for the mass production of ventilators. STARK Industries was awarded a global license […]