Aura Personal Air Samplers for NIOSH Canister Method 3900

The National Institute of Occupational Safety and Health (NIOSH) has published their “Volatile Organic Compounds, C1 to C10, Canister Method 3900” in the NIOSH Manual of Analytical Methods (NMAM), Fifth Edition. In short, the method is a variant of United States (U.S.) Environmental Protection Agency (EPA) Method TO-15; however, with a focus on a particular subset of VOCs often encountered in the occupational setting at low ppm_v concentrations. So, why am I bothering to blog about this when we already have countless TO-15 blogs? Well, it just so happens that this long-awaited document is the first validated method for capillary flow-controlled sampling into evacuated canisters. Ta da!!! Queue the Aura Personal Air Sampler! Oh what, you do not know the Restek Aura? We can fix that…

A couple of years ago, we launched the Aura Personal Air Sampler kit (shown above) for the Environmental and Occupational Health/Industrial Hygiene market. The impetus was to provide a personal air sampling alternative, which overcomes some of the short-comings associated with active and passive (diffusive) solid sorbent sampling approaches. The heart of the Aura is a capillary flow controller, which will constantly sample at ~0.31 mL/min into a 400 mL canister over an 8-hour sampling duration. Think of the capillary flow controller like an elongated version of the critical orifice you may be familiar with in our soil gas and passive flow controllers. The biggest difference is that it achieves relatively constant flow rates (i.e., <10% change) well below anything the aforementioned devices can achieve. The other advantage is that we are talking about a sampling device light as a feather, especially when compared to standard flow controllers. This is canister-based sampling, so no need to know the atmosphere and select the appropriate sorbent, as required with other personal air sampling approaches. The Aura covers everything from C1 to C10. There is also no need for a mass-rich, power-dependent, noise-making, calibration-requiring sampling pump. You know, the same sampling pumps test-subjects despise wearing. See the photo below where I can freely move about with the confidence and comfort of full mobility, minimal weight addition, and no added noise. That’s it for now… Oh wait, the list of awesomeness associated with Aura continues. We ship all of the capillary units at pre-calibrated flow rates, so sampling with the Aura is about as easy as it gets. Okay, now I am done with the boasting.

Consider the following your Aura crash course:

1. Attach the capillary flow controller to a quick connect.
2. Attach the quick connect to the 400 mL canister.
   1. Sampling thereby commences.
3. Place the Aura into the Aura purse.
4. Affix to the sampling subject.
5. Wait 8 hours and then reverse the process.

Easy peasy…  As for post sampling, go ahead and analyze the Aura just like you would any other canister sample. And NOW… you can do all of the aforementioned with the confidence the approach is backed by NIOSH Method 3900. If you want to know more about Aura and just happen to be out in Minneapolis, Minnesota on May 20-22, be sure to stop by at the American Industrial Hygiene Conference and Exposition (AIHce). Aura will be featured at our vendor booth and the Learning Pavilion (Expo Hall) on May 21, 1130 – 1155 am.