Collecting high-quality soil gas samples in the field for TO-15 analysis is essential for generating reliable data. Yet in the field, the process can be time-consuming and prone to error. With our clients’ sampling challenges in mind, Merit Laboratories designed a helium shroud that makes soil gas sampling more efficient, accurate, and reproducible — without the need for tools or field calibration.
Designed for Field Efficiency
The Merit helium shroud was developed to simplify the work of field sampling professionals:
No tools, no calibration required – ready to use immediately.
Quick-connect ports – reduce setup time and minimize potential for error.
Self-contained transport kit – protects components in transit and makes it easy to carry into the field.
Dual helium meters – allow staff to monitor helium concentrations in both the shroud and the line.
Following the included instructions, field staff can be ready to sample in just minutes.
Key Components of the Merit Helium Shroud
Each helium shroud kit is equipped with everything needed for efficient field deployment:
Interior helium detector – measures helium concentration inside the shroud (% helium, thermal conductivity).
Exterior helium detector – provides a secondary measurement of helium concentration (% helium, thermal conductivity) for confirmation.
Exterior flow pump – calibrated to 200 cc/min, eliminating the need for manual syringe purging.
Interior flow controller connection – links directly to the exterior pump for streamlined operation.
Sampling access port – located at the bottom of the shroud for connecting the sampling line to the flow controller.
60 mL syringe – used to test for liquid in the well prior to sampling.
Helium tank – supplies helium to create the enriched atmosphere necessary for leak-checking and validation.
By packaging these components together, Merit ensures that field staff arrive with a complete, ready-to-use system.
Field-Proven Results
The Merit helium shroud isn’t just a laboratory innovation — it’s been applied successfully in the field for years. Clients across the United States, from California to New York, have used the shroud to streamline soil gas sampling and improve data defensibility.
By testing the sampling chain and well in a helium-enriched atmosphere, environmental professionals can verify that no air breakthrough has occurred, ensuring that a valid soil gas sample is collected. Importantly, helium does not interfere with the laboratory analysis of target volatile organic compounds, making it a reliable tracer for soil gas sampling projects nationwide.
Technical Advantages of the Merit Helium Shroud
The helium shroud improves both the reliability and defensibility of soil gas data:
Verification of sample integrity – By testing the soil gas sampling chain and well in a helium-enriched atmosphere, users can confirm that no atmospheric breakthrough is occurring.
VOC compatibility – The presence of helium does not interfere with laboratory analysis of target volatile organic compounds.
Simplified purging – Unlike other systems that require manual syringe purging at a controlled flow rate, the Merit shroud integrates a pump calibrated to 200 cc/min. Users simply flip a switch and start a timer—removing guesswork and reducing variability.
After each field deployment, every helium shroud is returned to Merit, where it is inspected, cleaned, tested, and repackaged for transport.
Best Practices and Project Support
When setting up an air project, we encourage clients to contact Merit early in the planning process. Selecting the appropriate sampling media is critical to meeting project-specific data quality objectives, including target compound lists and reporting limits. Our technical team is available to help you match the right equipment and methods to your project goals.
Merit Laboratories is committed to making soil gas sampling easier, more accurate, and more defensible. With tools like our helium shroud and a full range of air sampling media solutions, we’re here to support your environmental testing needs.
Merit Laboratories is one of the nation’s leading environmental testing laboratories, analyzing air, soil, wastewater, groundwater, drinking water, and other sample matrices for a diverse range of analytical parameters. Merit is designated as a Small Business Enterprise (SBE) and Woman-Owned Business Enterprise (WBE).