Hacker News Reader

Indeed, that one doesn’t appear to. There are plenty of standalone kits that do as it’s used to prevent boiler corrosion, however. Here’s an example:

https://www.chemetrics.com/product-category/test-kits/hydraz...

I don’t know if there are any “all in one” tests that include it but I’m not involved in the field in any way aside from using a reverse osmosis filter on my tap.

"That vendor doesn't mention hydrazine ..."

You are correct.

I'm surprised it isn't in the "ultimate water test" and I assumed that it was.

The article states these other companies played a role in faulty pH measurement, leading to less dilution with actual real water.