Does the Vapor Pin® sampling device provide a tight seal against the slab?
Under normal circumstances with proper installation through a concrete slab, the Vapor Pin® sampling device provides an air-tight seal. Cox-Colvin has leak tested the Vapor Pin® sampling device with helium; with 99% helium in the leak-test shroud, no helium (<50 ppm) was detected in soil gas. In some situations, such as a thin concrete slab or cracked and degraded concrete, or a hole greater than 5/8-inch diameter, may result in a poor seal. We recommend leak testing as part of the sampling procedure.
