Application and Design Flexibility

Fig 1 is a schematic diagram of a typical moisture controlled static eliminator showing exactly how it works. You can see that column of moist air circulates only to the targeted designated area that you want. There is no leakage of moist air due to the control of pressure both at the inlet and outlet of the air stream with higher suction power at the outlet and lower blowing power at the inlet airstream.
Fig. 1

Specifically, the detection of the presence of the airstream leakage can be verified using a pair of RH meter as illustrated in the Fig 2.

Fig. 2 (Air Passage Leakage Test)

Fig 3 is another version showing how the flow of airstream can be effectively controlled without the leakage into the surrounding work area.

Fig 4 shows the various possible designs or a combination of the designs that can be fully investigated to optimize the use of the current RH Static Eliminator technology as disclosed in this papers. 
Fig.4(a)                                                                    Fig.4(b)

Fig.4(c)                                                                      Fig.4(d)

                           Fig.4(e)                                                            Fig.4(f)

Technically, static charge mitigation process is merely a delivery of a stream of moist air to the insulative parts to convert the insulative parts to static dissipative behavior (momentarily) where any static charge will be instantaneously and naturally drained to any metallic structure where the parts rest on and subsequently to ground. 

In other words, skillfully controlled column of humid air stream provides a static dissipative grounding path momentarily (or permanently) for ESD sensitively devices and assembled PCB to instantly drain unwanted static charge safely to ground. 

The targeted spots of static charge neutralization are often moving microchips or moving assembled PCB parts which mainly consist of insulator (moulding compound, polycarbonate, etc) and metallic conductor of IC lead frame and PCB conductive traces prior to the testing point. 

Momentarily exposing the parts with moist air on the exterior surfaces will not cause penetration of moist air inside the parts materials. 

Therefore, the tiny amount of only few molecular thick or less layers of moisture on the part surfaces will quickly escape back into the ambient RH environment after passing through the narrow column of RH controlled airstream. 

There is no condensation of moisture residing on the part surfaces. Condensation will take place only if there is substantial temperature difference AND the prolong exposure between the very dense humid air and the targeted part surfaces. 

It is just like blowing a mouthful of warm moist air onto our "cool" eye glasses and quickly see it evaporating into the air within seconds with nothing left on the eye glasses.