If you review the TTField information, you can see that the fields these devices emit are much stronger and at lower frequency bands. For instance, a smartphone held 5 cm away emits roughly 0.025 V/cm, whereas the helmet we're discussing hits you with anywhere between 1.0 and 3.5 V/cm. So the lower band is about 40 times stronger than a smartphone held against your temple!
Wireless headphones emit 10-400 times less energy than smartphones do. My personal takeaway is that you're safe.
3 orders of magnitude of margin in terms of power is still way less than I expected, considering that I have these devices on my head for 3 order of magnitude more hours than people using that treatment.
Of course there are dose effects and non linearities so we should very very likely be good. But huh.
Wireless headphones emit 10-400 times less energy than smartphones do. My personal takeaway is that you're safe.