def ReducedElectricalField ( E, p=101325, T=293.15 ):
    """Reduced electric field strength calculation using ideal gas law.

    Args:
        E       :   Electric field.
        p       :   Ambient pressure during discharge.
        T       :   Ambient temperature during discharge.        

    Returns:
        Returns the reduced electric field strength.
    """

    kB = 1.3806485279e-23   # Boltzmann constant (J x K^-1)
    N = p / ( kB * T)       # Particle density per cubic meter (m^-3)
    Td = E / N              # Calculate the reduced electrical field strength
    return (Td/10e-21)      # Normalise