Author Archive

The New U.S. EPA Method TO-15A Blog Series-Part 5: Humidification

In the previous blog (https://blog.restek.com/the-new-u-s-epa-method-to-15a-blog-series-part4-clean-lines-for-clean-air/) I left off with our system at or under the 20pptv limit required by the new TO-15A method after replacing and moving our air fill line. Once you’re sure of your air quality and the cleanliness of your lines the next step is filling and humidifying your canisters, and if […]

The New U.S. EPA Method TO-15A Blog Series-Part4: Clean Lines for Clean Air

In previous blogs (Part 1, Part 2, Part 3) we’ve covered the need to use air instead of nitrogen as a fill gas, the new lower blank requirements, and how these increase the importance for very clean lab air for canister filling. We’ve shown that using high quality gas filters or generators will get you […]

Cryogenic Cooling for Air Analysis Part 2 – Combining TO-15A and Ethylene Oxide

In my previous blog on cryogenic cooling (https://blog.restek.com/cyrogenic-cooling-for-air-analysis-interferences-from-n2-co2-and-o2/) I touched briefly on ethylene oxide (EtO) and why it may be of interest in ambient air analysis. While OSHA has a time weighted average (TWA) limit for EtO at 1ppm for an 8 hour exposure, recent work by the US EPA has shown that even low […]

Cryogenic Cooling for Air Analysis – Interferences from N2, CO2, and O2

Spring is already here and summer is just around the corner and soon we’ll be trying to stay cool.  For those of us doing ambient air analysis though, keeping cool can sometimes mean cryogenic cooling. While our VMS columns can easily separate the TO-15 compounds with no need for cryo cooling (see https://blog.restek.com/air-columns-part-iii-my-favorite-column-phase-for-epa-method-to-15/) there are […]

Pro EZGC Library Update – Azo Dye Aryl Amines

Azo dyes are commonly used in many products, including food, textiles, and paints. In some azo dyes the azo functional group (R-N=N-R’) can be broken in reductive conditions to form carcinogenic aryl amines. The use of these dyes is regulated in the EU under the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) regulation instated […]

Pro EZGC Terpene Libraries Update

Whether you’re doing testing for cannabis, hops, or other food and fragrance analysis, you probably have an interest in terpenes. Now, to help out with that analysis we’ve updated our Pro EZGC libraries with 60 terpenes and terpenoids for the Rxi-17 and Rtx-200 columns. Compound CAS# Compound CAS# alpha-Pinene 80-56-8 Menthone 89-80-5 Isovaleric acid 503-74-2 […]

TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683 Part 3: Formaldehyde Sampling in Air Canisters

In my previous blog (TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683 part 2: Deans switching and TO-15/PAMS) I covered the combination of the TO-15 and PAMS (or HJ759 and PAMS) methods into a single run using a Deans Switch and FID/MS detector set up. I said that I’d revisit integrating […]

TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683 part 2: Deans switching and TO-15/PAMS

In a previous blog (TO-15 + PAMS + TO-11A = China’s HJ759 + PAMS + HJ683) Jason Herrington mentioned a dual column MS/FID setup for China’s combined HJ759 + PAMS + HJ683 method. While this could be done with a simple Y splitter (such as https://www.restek.com/catalog/view/1983), a more elegant solution is to use a microfluidic […]