This is the ratio between the peak level of an acoustic signal and its energy equivalent, or rms, level. For a continuous sine wave the peak level is 3 dB higher than the rms level when measured in logarithmic terms. When measured in linear unit terms the peak level is 1.41 (square root of 2) times the rms. value. For an impulsive signal such as a blast or an impact sound the peak level can easily exceed the rms level by 25 or 30 dB.