Did you try using Google?
For example, in pharmaceutical production, our standards are called the USP: US Pharmacopoeia. There are others, JP, EP, RP and nations are working to harmonize them. If I use Google, I can find a copy of the older version of the USP. There are only slight changes from year to year. But no one will buy pharmaceuticals manufactured by someone who isn't using the current version. The fact that I can find an older version, or heard about it from someone else, really doesn't say anything.
ACS silver nitrate is sold by Sigma Aldrich at >99.0% purity:
grade ACS reagent
vapor density 5.8 (vs air)
assay ≥99.0%
form solid
clarity of soln passes test
impurities Free acid, passes test
≤0.01% not HCl pptd.
mp 212 °C (dec.)(lit.)
anion traces chloride (Cl-): ≤5 ppm
sulfate (SO42-): ≤0.002%
cation traces Cu: ≤2 ppm
Fe: ≤2 ppm
Pb: ≤0.001%
If your non-accredited lab tests your product, and find that its 99.9999% pure, with say, 0.02 ppm Cu, that is likewise meaningless, even though the numbers "seem" better. No one will pay the same price for yours, and if they claim their process uses ACS grade reagents, they'd be lying if they used yours. No one will take this chance.