Helium Shroud and Shut-in Leak Check Video
With the recent changes and advances that have emerged through the updates and final versions of the U.S. Environmental Protection Agency’s (U.S. EPA) Vapor Intrusion Guidance documents, it has become more evident that proper sampling techniques are important considerations for those in the regulated community performing field investigations.
Alpha Analytical understands the challenges and confusion that exists within the industry as it relates to performing precise and accurate Vapor Intrusion and Petroleum Vapor Intrusion field investigations and sampling events. Since the U.S. EPA and many states agencies are now requiring or recommending Quality Assurance Plans (QAPs) as part of Vapor Intrusion investigations, following the best practices when collecting field data is more critical than ever.
An area of particular attention is minimizing sample dilution by influent air leaking through connections during sample collection resulting in false negatives. Shut-in check & Helium leak checks demonstrate the integrity of the above ground assembly connections and vapor probe surface areas prior to sample collection. If Helium Leak checks performed on the initial probes demonstrate sample integrity, the investigator may consider reducing the number of probes tested.
Alpha Analytical has produced this video demonstration to illustrate how to perform a Shut-in check and Helium Leak check using a surface vapor shroud.
Disclaimer: The directions portrayed in this video are intended to supplement users’ standard operating procedures for conducting field sample collection. Alpha Analytical provides this as a service and is not directly or indirectly responsible for the field performance of these checks. The components are supplied from laboratory vendors and it is recommended that they are stored in an environment free from VOC sources prior to single use. Any substitutions of components should be checked before use as they may affect the performance of the checks.