The five types of white cells and the approximate percentage they make up in the blood are: 1  Neutrophils (55% to 70%) 2  Band neutrophils (0% to 3%) 3  Lymphocytes (20% to 40%) 4  Monocytes (2% to 8%) 5  Eosinophils (1% to 4%) 6  Basophils (0.5% to 1%)
A sound level meter is an instrument that can measure sound level, commonly used in noise pollution studies for the quantification of different kinds of noise, especially for industrial, environmental and aircraft noise. common variant of the sound level meter is a noise dosemeter (dosimeter in American English). However, this is now formally known as a personal sound exposure meter (PSEM) and has its own International standard IEC 61252:1993.
These are electronic filters within the the instrument that are used to adjust the way in which the instrument measures the noise. The most commonly used Frequency Weightings that you will see on a modern sound level meter or noise dosimeter are âAâ, âCâ and âZâ and below is a brief explanation of each of these.