r/analyticalchemistry

I work in a HIGHLY regulated field, so when I began asking questions about the accuracy and precision of the clearance devices, I was told that has not been asked in 27 years. Here is what is making me very uneasy… devices are supposed to read <1 ppm per the EPA, which the EPA “regulates”, but they don’t regulate the accuracy of said devices or what devices are used. The EPA lists the reliability and accuracy on a few devices deeming some effective or non effective. Similarly, the ACB has found that many devices are not accurate below 3 ppm and also indicate that humidity and other field variables can alter the accuracy. These devices are also only calibrated annually, and from what I can find, do not have any sort of routine quality control.

The device being used by the company I hired is the SF-ExplorIR, which literally has an accuracy of 0 and a minimum false positive rate of 38% (and is listed as non-effective by the EPA). When I began asking questions about this, I could tell the sales guy did not understand so I stopped asking. The irony that the EPA requires readings to be <1 ppm, yet does not regulate the accuracy of these meters is blowing my mind and more importantly fueling my fear. How do we know that people are going back into their houses at safe levels? I can assume based on the studies I’ve read, that if a meter reads <1 ppm, it is at least not above 3 ppm. OSHA limits are 5 ppm for 8 hours but the magnitude of these numbers mean nothing to me so it’s hard to understand the threshold of safe versus toxic. Can someone please tell me something that will comfort me regarding the analytical standards of the clearance devices? I have a 1 year old daughter, my house is getting fumigated in 2 days, and I’m actually terrified to bring her back in with blissful ignorance that 1 means 1.

Thanks in advance!

Edit: since I am crossposting, I will add that I am referring to clearance readings of sulfuryl flouride for fumigation of termites. Lastly, I live in the south east region of the US.

Hi everyone,

we would like to buy some standards of synthetic cannabinoids and NSOs, but Cayman is quite expensive for us (at least for now).

Do anyone have experience with LGC Chemicals distributor and brands like TRC or LoGiCal (sold by LGC)?

Any comments will be appreciated, thank you!

Have a nice day!

I’ve got a solution with an unknown amount of Cu- and Fe-Ions which I need to determine the total mass of. I’ve tried masking the Fe with tartrate to do an iodometry which didn’t work. I’ve also tried to Analyse the amount of iron by doing a KMnO4-titration (Reinhardt-Zimmermann), which also didn’t really work. I’ve been struggling for 3 days on this now, so if anyone knows a good way to do this quantitative analysis, please let me know. Thanks a lot in advance!