A low-level electric current is applied to the test area. The positive electrode is covered by gauze and saturated with pilocarpine (a drug that stimulates sweating). The negative electrode is covered with gauze and saturated with bicarbonate solution.
A current is applied for 5 to 12 minutes, and a paper disk is then placed over the test site and covered with paraffin to obtain an airtight seal. After 1 hour, the disk is transferred to a weighing jar, then put in water to dissolve the salts. This solution is then analyzed for chloride.
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