Clark D21

Two portable leak detectors are available for helium leak testing on vacuum systems or parts.  Both detectors are equipped with carts for easy transportation; please consult with the facility staff if you would like to use one outside of the Physical Sciences Complex.  Users may borrow a helium cylinder and/or a regulator/flow meter/spray gun assembly for testing purposes.  Both detectors include a ‘sniffer’ accessory for detecting outflow of internal helium, e.g. from cryogenic systems.

The Varian 979 uses a rotary vane backing pump and may be used on any vacuum system or part.  It is capable of detecting leaks down to 10^-9 atm-cc/sec.

The Pfeiffer ASM 340 uses a scroll pump and may only be used on vacuum systems or parts that have not been pumped with oil-based pumps; users must consult with the facility staff to discuss this requirement prior to use and to receive authorization.  In addition to ⁴He, it can also detect ³He and H₂. It is capable of detecting leaks down to 10^-13 atm-cc/sec.

Pfeiffer ASM 340 product page

Standard Operating Procedure

For rates information, please see the rates page.