non-ionizing radiation hazard safety area, danger warning text sign sticker label, large icon signage, black triangle

adverse advice alert area attention beware biological black carcinogenic careful caution closeup current damage danger dangerous effect effects electrical electricity electromagnetic electron energy excitation field fields frequency hazard health heating high icon induced industrial industry infrared intense ionizing isolated label large light low macro microwave non notice optical pictogram power protection radiation radio radiofrequency risk safety sign signage signal spectrum static sticker symbol technology text thermal triangle triangular unsafe visible warning wavelength waves yellow zone