Topic summary

A report I filed that turned out to be wrong, and the correction

Sourcing › Vendor reports certificate of analysis disputed third-party testing

This is a generated summary. It shows the 9 most-liked posts from a topic of 133, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

c.chowdhuryTL2 Moderator16 Apr 2025 · edited#16

On post #12 — agreed on the reasoning, with one qualification.

What "verified" means on our pages: specific lots were independently measured on stated dates by named services and results were consistent with the supplier's documentation. It is not a recommendation and does not extend to untested lots.

31 likes 15mo

y.adeyemiTL2 Moderator9 May 2025 · edited#45

31 likes 15mo

g.ekstromTL2 Moderator26 May 2025#71

Pattern across lots: a single result is a data point. Three or four results from the same supplier showing a consistent pattern becomes a record worth discussing. Two results that disagree might just be measurement variation.

26 likes 14mo

desiccant_notesTL2Member1 Jun 2025#80

I read post #78 twice before replying, because I had assumed the opposite.

Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive.

27 likes 14mo

GEldridgeTL3Regular3 Jun 2025#84

post #83 answers the question as asked. The question underneath it is different.

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

30 likes 14mo

s.duarteTL2 Moderator16 Jun 2025#106

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

31 likes 13mo

b.jankowiakTL3Regular20 Jun 2025#112

j.dahlberg, post #108: I read post #106 twice before replying, because I had assumed the opposite. Multiple services on one lot: agreement across two independent laboratories is stronger than a high number from one. Our vendor pages deliberately mix services for that reason. Go to post

28 likes in reply to #108 13mo

y.asanteTL2 Moderator24 Jun 2025#119

slow_titrator, post #116: Temporal patterns: if results from a supplier were good two years ago but have deteriorated recently, that is information. If they have been consistent over years, that is also information. Go to post

29 likes in reply to #116 13mo

chromatogramTL4Analytical chemist29 Jun 2025#128

desiccant_notes, post #80: I read post #78 twice before replying, because I had assumed the opposite. Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive. Go to post

On post #124 — agreed on the reasoning, with one qualification.

29 likes in reply to #80 13mo

Read the full topic (133 posts)

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