β-ray dust concentration measuring apparatus and method for confirming validity of sample used therein

摘要

A beta-ray soot concentration direct readout monitor and a method for determining effective sample are disclosed. The monitor comprises a fume collection cell and a fume mass detection cell. The fume collection cell includes a fume sampling gun, a filter paper (3) and a mechanical control auto form feed structure. The fume sampling gun includes a gathering tube (11), a pitot tube (12) and a sheath tube (13). The gathering tube (11) tail of the fume sampling gun is equipped with an upper cavity body (21) and correspondently equipped with a lower cavity body (22). The filter paper (3) passes through space between the upper and lower cavities body (21,22). A paper supporting gate (23) is provided at the inlet of the lower cavity body (22). A smoke outlet (23) is equipped at a lower part of the lower cavity body (22). Wherein, the sampling acreage (31) of the soot acquired from the upper cavity body (21) is at least twice with the actual testing acreage (31) of the filter paper (3).