Helium is the best choice of tracer gas to find leaks for a number of reasons. It is non-toxic, inert, non-condensable, non-flammable and not normally present in the atmosphere at more than trace amounts (5 ppm). Due to its small atomic size, helium passes easily through leaks.
Quality control of production parts and assemblies using helium leak detectors can help assure the integrity of your production process. Typical examples include: hermetically sealed packages, valves, manifolding, seals, vacuum vessels and systems, medical devices, high purity piping, brake lines, fuel lines, hydraulic lines, refrigeration assemblies, radiators, heat exchangers, condensers, storage tanks.