Description: logarithmical measure of the pressure of a sound wave relative to a reference level; Name: acoustic pressure level
Description: Ten times the logarithm to the base 10 of the ratio of the square of the sound pressure, p, to the square of a reference value, p0, expressed in decibels; Name: Sound pressure level
Description: Speed that characterizes a pump in terms of its speed, flow rate per impeller eye, i.e. total flow for single-flow impeller, half flow for double-flow impeller, at the best efficiency point and head per stage at maximum impeller diameter ; Name: Specific speed