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20 SMT007 MAGAZINE I NOVEMBER 2021 Feature Article by Eric Camden FORESITE, INC. If I may begin this article with the tired trope of using a dictionary definition for "objective evidence" from a scientific perspective: "To be termed scientific, a method of inquiry must be based on gathering observable, empirical, and measurable evidence subject to specif- ic principles of reasoning. A scientific meth- od consists of the collection of data through observation and experimen- tation, and the formulation and test- ing of hypotheses." 1 Applying this definition to J-STD- 001H, Section 8.0 (the titular three pages) we get an idea of what it takes to meet this new requirement. ere has been much gnashing of teeth and furrowing of brows since the historical ROSE testing limits of 1.56 µg/cm 2 of sodium chloride equivalence was removed from the J-STD-001 back in 2020. is position is quite understand- able as that has been the only indus- try accepted standard for measur- ing PCBA ionic cleanliness since the 1970s. Let's pause here and think about that last phrase. e criteria was developed in the 1970s when as- semblies were built with rosin flux- es containing ~35% solids and were subsequently cleaned with ozone de- pleting chemicals. is was a time of gas guzzling land yachts and muscle Three Pages That Changed the World (Kind Of) cars, bell bottoms, platform shoes, and pork- chop sideburns. We have moved past most of those (sadly for those sweet sideburns), but as other electronic technologies changed, the testing criteria did not. ink about how much has changed since the 1970s in terms of PCBAs, their components, and how they are built. Figures 1 and 2 give you a rough idea of the astronomical leaps the industry has made in both processing power and miniaturization. Figures 1 and 2: PCBAs from the 1970s and today 2 .