1. Not a great situation to be in. Therefore, when targeting areas of the head, use the areas of the shoulders for pad placement. As this gets the electricity closest to the area to be targeted safely.
2. It is really not suggested to use it over the shoulders. It is suggested so to not to trigger the muscles to contract. That may be dangerous in that area. However, I had many occasions in my family when it had to be used on the face to be efficient. So I just set up a minimum frequency limit of around 50 kHz. The muscles are not fast enough to react on even 15-20 kHz, so it seemed to be a safe limit. All I can tell you that it felt perfectly like nothing but was still effective. However, be sure you know what you do if you plan to experiment! Read the manual about the frequency lower and upper limits, and try the pads first under the shoulders. And still, avoid the heart, that is a chaotic electrical organ, that may still be affected even by high frequencies.
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