355.2 Hz is one of Barbara Hero's isotope tones, associated with hydrogen and rendered through the Pythagorean Lambdoma's whole-number ratios. The same pitch also turns up in her planetary-grid work, one of the meeting points where her isotope and planetary families land on a single tone. Both links belong to Hero's Lambdoma framework, a contemplative, numeric way of listening across scales, never a measurement of radioactivity or geography. Alongside her elemental tones, Barbara Hero derived a family of pitches she associated with isotopes: uranium, thorium, radium, plutonium and their kin. Rendered through the Lambdoma's whole-number ratios, each becomes a distinct audible tone. As with all of Hero's work, the correspondence is an artistic and numeric system, offered for listening rather than as a measurement of radioactivity. Independent of any tradition, controlled clinical evidence that a specific frequency produces a specific health effect is limited and mixed. Auriviel presents these tunings as music and contemplative practice. This page is for general information and relaxation. Auriviel's frequency music is not medical advice, diagnosis, or treatment, and no health outcome is claimed. If you have a medical concern, please consult a qualified professional.