Product Description
Rather than performing a traditional vacuum sampling event, MiniCans and Bottle-Vacs™ are initially filled with helium, or helium with a recovery surrogate, and active sampling occurs in response to the controlled exchange of helium with air through a diffusion region. An HDS™ diffusion zone’s internal diameter is 20–50 times larger than typical critical orifice samplers, so particulate plugging is virtually impossible. HDS™ eliminates the need for sampler calibration, as relative diffusion rates of Helium and air are virtually constant. And unlike passive sampling with tubes – where compounds lighter than Benzene are not recovered quantitatively – HDS monitoring recovers all compounds heavier than Helium.