def relaxation_frequency_oxygen(pressure, h, reference_pressure=REFERENCE_PRESSURE):
    return pressure / reference_pressure * ( 24.0 + 4.04 * 10.0**4.0 * h * (0.02 + h) / (0.391 + h) )
Relaxation frequency of oxygen :math:`f_{r,O}`.
dataset/ETHPy150Open python-acoustics/python-acoustics/acoustics/standards/iso_9613_1_1993.py/relaxation_frequency_oxygen