What is isokinetic source sampling? Webster's dictionary defines iso as denoting equality, similarity, uniformity. Kinetic is defined as, pertaining to, or due to motion. Isokinetic sampling is an equal or uniform sampling of particles and gases in motion within the stack.
Isokinetic source sampling is achieved when the velocity of gas entering the sampling nozzle is exactly equal to the velocity of the approaching gas stream. This provides a uniform, unbiased sample of the pollutants being emitted by the source. Isokinetic source sampling most closely evaluates and defines various parameters in the stack as they actually exist at the time of sampling.
Preliminary measurements are made in order to determine the appropriate sized nozzle for isokinetic sampling across the velocity profile of the stack. Minor adjustments required to maintain an isokinetic condition at each test point are accomplished by regulating the sample flow rate.
Source Testing (44 KB)