Ruggera memo, April 1991 FDA Special Product Engineer Paul Ruggera was assigned to evaluate
the GHR electric tweezer in the course of their 510(k) review.
 Stephens 1990
After verifying the device's output was within stated parameters,
Mr. Ruggera performed a test of the amount of energy being delivered
to a hair. He tested hairs on his right forearm according to manufacturer
instructions. Each hair tested when grasped according to instructions
presented a resistance of 0.5 M to 1 M ohm. When the tweezers
touched his skin that had been wetted with the manufacturer's
electrolytic solution, the resistance jumped to about 30 k ohm,
or about two orders of magnitude greater. Ruggera concludes with
the obvious question any electrical engineer would ask:
"Does this energy get to the hair follicle, or is it merely
dispersed when it meets the lower resistance of the wetted skin
surface area?"
This sums up the basic flaw in the theory and practice of electric
tweezing: any energy traveling down a hair will disperse across
the skin rather than continue down the hair. This is called "the
path of least resistance," and it's one of the most basic
laws of electricity. Electricity travels on the most conductive
path available, and since skin is much more conductive than hair,
electricity from an electric tweezer will simply disperse across
the skin. This is even more true when skin is coated in conductive
gel, as shown in Schuster, 1992.
FDA stated in 1998 that there is no body of significant information
establishing the effectiveness of electric tweezers to permanently
remove hair. FDA's decision has left some unanswered questions
about the status of what GHR can and cannot claim. I have analyzed
this faulty submission and reported my findings to FDA in a petition
for administrative reconsideration.
Download my full GHR petition from
FDA's website (warning: very large Adobe Acrobat file)
http://www.fda.gov/ohrms/dockets/dailys/052699/prc001.pdf
99P-1615 PRC for K905125 Guaranty Hair Removal System by Stephens
Mfg
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