Helium Shroud -An industry standard

Helium Shroud -An industry standard

Our team of scientists here at C&T are passionate about moving the field of testing forward and putting our skills to use for the field as a whole in addition to doing it for our clients.

The case study presented below is an example of just this type of approach. While the initial work was spurred by a single client, this process has now become an industry standard due to both its efficacy and our interest in improving sampling and testing procedures.


C&T’s client, a large environmental remediation engineering company wanted a new process for sampling soil gas wells. Ideally, it should be a compact, lightweight, fast, efficient and easy-to-use test kit for in-the-field testing in real time. No small order!


C&T designed and built a prototype soil gas well sampling shroud incorporating its sampling trains in a novel closed atmosphere design with lightweight Helium supply, specialized quick connect and 3-way stainless steel valves and two proprietary palm sized battery powered helium detectors. C&T created a kit that included all materials necessary for a two-person crew to sample 8-12 soil gas wells under Helium in an 8 hour day.


C&T continued to enhance the prototype so that it surpassed all of the initial specifications and was easier to use. In addition to the single sample per well initial design, we developed a leak detection shroud for duplicate samples and sampling the same well at different depths. Training procedures and methods to determine and correct leaks in the field were developed and documented.

The shroud system was presented to California regulators in the spring of 2011 and shortly thereafter these regulators began routinely requiring the use of Helium leak detection systems for soil gas sampling projects. CA Department of Toxic Substances Control (DTSC) published C&T’s shroud design paper on its website  and reproduced a generic design based on C&T’s shroud in the 2012 version of their soil gas sampling guidelines. The shroud was described in a paper presented by C&T scientists at the National Environmental Measurements Conference (NEMC) in August of 2011. C&T has collaborated with a major supplier of air sampling equipment to manufacture and sell the shroud in three configurations to other users around the country. As of summer 2012, C&T’s shrouds have been employed for sampling nearly 1,800 soil gas wells at more than 60 sites around the USA.

Today C&T has an inventory of two dozen single train and several additional duplicate and dual depth Helium leak detection shrouds available to assist clients complete their soil gas sampling projects. C&T’s shroud is recognized by the majority of soil gas samplers as the easiest to use, most compact, lightest, and most efficient commercially available soil gas helium leak detection system.