KNF (Trenton, NJ) double-diaphragm, oil-free pumps are designed for the safe transport and evacuation of costly, high purity, rare and/or dangerous gases. With a patented double diaphragm system, the primary diaphragm does the work, while the safety back-up diaphragm keeps gas from escaping in the event of a failure. Additionally, the pump is designed to prevent contamination from external influences. Numerous cost-effective options are available, including active inter-diaphragm leak monitoring, material and motor choices, and multiple levels of leak testing. These pumps are particularly well-suited for many chemical, nuclear or process engineering applications including: gas sampling and monitoring, cryostats, pulse tube and dilution refrigeration, and helium liquefiers.