modifying the operating conditions during analysis of the gas by controlling the temperature the sticking probability is reduced thereby reducing the particle growth process a wide variety of compressed gases are suitable for use in the present invention suitable gases include electronic specialty gases 34 esg 34 which are typically contained in gas cylinders at a wide range of pressures up to 3000 pounds per square inch 34 psi 34 200 bar metallic impurities in esg 39 s are of critical concern in micro electronics manufacturing processes suitable gases include inert gases such as n 2 ar he and the like etchant gases such as cl 2 hcl bcl 3 hbr sf 6 cf 4 c 2 f 6 and the like and reactive gases such as sih 4 sih 2 cl 2 nh 3 other gases compatible with system materials and the like the preferred temperature setting depends on the type of gas the cylinder pressure and the withdrawn flow rate the temperature setting is directly related to the withdrawn flow rate the higher the flow rate the higher the temperature setting that is required to evaporate the artifact particles the preferred temperature setting can be determined individually as described below for each application and preferably does not exceed 250 u00b0 c the temperature is set at a predetermined preferred temperature and the system is allowed to reach equilibrium at the intended sampling flow rate prior to actual sampling a temperature control device is provided in combination with the pressure balancing device described in u s pat no 5 209 102 which is incorporated herein by reference in its entirety as shown in fig2 referring to fig2.