3 ms·

I think these reference materials are more about how they’re well-characterized, right? It’s peanut butter, sure, but it’s not meant to be the peanut butter or

by bonyt 3y ago

I think these reference materials are more about how they’re well-characterized, right? It’s peanut butter, sure, but it’s not meant to be the peanut butter or even represent any particular peanut butter. Instead, it comes with a detailed document describing all of the kinds of measurements you could take on it and their expected results. If you’ve got a peanut butter testing machine, you can put some in there and make sure it spits out the same result. So, you’re not comparing any peanut butter against it, just your machine’s results against the results expected.

pdq 3y ago
Exactly. This is akin to selling a calibrated 1 kilogram cube of lead, with a precision of 1 nanogram and specified purity, for $1000. You are not just buying an overpriced $3 block of lead, but one that can be precisely used for calibrating machines, equipment, or processes.
op00to 3y ago
It’s exactly the same peanut butter time after time, which also adds complexity! It’s easy to make peanut butter. It’s difficult to make each batch “chemically” identical! (Yes, chemically identical is impossible in a product like peanut butter, but identical enough for the purpose)
jwestbury 3y ago
Correct. Veritasium actually did a video on exactly this set of items last year[0]. The tl;dr is that NIST has a large collection of items which are rigorously produced and tested, with detailed documentation about their composition and test results, which allows companies to test their own products to very specific standards. For instance, peanut butter has aflatoxins -- known carcinogens. NIST's standard peanut butter has known levels of aflatoxins. By purchasing this peanut butter and testing it on your own peanut-butter-aflatoxin-sensing machine, you can calibrate your machine to detect aflatoxins in peanut butter to a reasonably high precision. 0. https://www.youtube.com/watch?v=esQyYGezS7c https://www.youtube.com/watch?v=esQyYGezS7c

by bonyt 3y ago

pdq 3y ago

Exactly. This is akin to selling a calibrated 1 kilogram cube of lead, with a precision of 1 nanogram and specified purity, for $1000. You are not just buying an overpriced $3 block of lead, but one that can be precisely used for calibrating machines, equipment, or processes.

op00to 3y ago

It’s exactly the same peanut butter time after time, which also adds complexity! It’s easy to make peanut butter. It’s difficult to make each batch “chemically” identical! (Yes, chemically identical is impossible in a product like peanut butter, but identical enough for the purpose)

jwestbury 3y ago

Correct. Veritasium actually did a video on exactly this set of items last year[0]. The tl;dr is that NIST has a large collection of items which are rigorously produced and tested, with detailed documentation about their composition and test results, which allows companies to test their own products to very specific standards. For instance, peanut butter has aflatoxins -- known carcinogens. NIST's standard peanut butter has known levels of aflatoxins. By purchasing this peanut butter and testing it on your own peanut-butter-aflatoxin-sensing machine, you can calibrate your machine to detect aflatoxins in peanut butter to a reasonably high precision. 0. https://www.youtube.com/watch?v=esQyYGezS7c https://www.youtube.com/watch?v=esQyYGezS7c