Question

Before placing the electrodes the skin should be __________

(a) wet

(b) dry

(c) hairy

(d) oily

I had been asked this question in an interview for job.

Enquiry is from Electrodes for ECG in section Bioelectric Signal and Electrodes of Biomedical Instrumentation

Answer 1

Before placing the electrodes for an ECG, the skin should be:

(b) dry

Dry skin ensures better adhesion and proper conductivity between the skin and the electrode, enhancing the quality of the signal by reducing impedance. Additionally, the skin is often cleaned and sometimes shaved to remove oils or hair that might interfere with the electrode’s contact.