Helium Diffusion Sampling (HDS) personal monitors are wearable, small, and can be used for TO-15, along with other indoor air testing.
ALS has a new sampling device that simplifies sampling for volatile organic compounds (VOCs) in ambient and indoor air. Helium Diffusion Sampling (HDS) personal monitors are wearable, small, and can be used for TO-15, along with other indoor air testing.
The size of the device makes it much more convenient to carry than summa canisters and saves shipping costs. The samplers are also extremely reliable, providing detection limits five to seven times lower than organic passive badges or monitors.
Based on breakthrough helium diffusion technology, an HDS sample is collected by creating a vacuum that actively pulls air in as helium escapes. Before going to the field, each HDS monitor is vacuum-cleaned and pressurized with helium at 5–10 psig. The helium also contains a PPM level surrogate chemical called Bromofluorotoluene (BFT) to confirm leak-free operation and ensure the inertness of every sampler by monitoring BFT recovery.
ALS also offers a pressure gauge to confirm a positive helium pressure prior to sampling to verify unwanted sampling into the HDS personal monitor has not occurred. This pressure is measured and recorded at the time of sampling as proof of sampler integrity.
To take advantage of this new technology, contact your ALS project manager or our environmental laboratory in Salt Lake City, Utah, USA.
Features & benefits
- Grab sample options, 15 minute or 8 hour
- Incredibly easy to use
- Small and portable
- Save on shipping costs
- Convenient carrying case that clips to clothing
- No pumps, batteries, or selection of media
- Same approach for all sample concentrations and compounds
- No breakthrough or recovery concerns
How does Helium Diffusion Sampling work?
The vacuum created by escaping helium actively draws surrounding air into the sampler. This active air sampling prevents any loss of compounds through reverse diffusion and substantially normalizes uptake rates of all compounds despite differences in diffusion rates.
Sampling starts when the control valve is removed and stops when the valve is reattached.