Abstract: The disclosure is of an improved method and apparatus for humidifying medical gases. The apparatus improved is of the type which comprises a portable housing enclosing a water reservoir, a gas chamber, gas inlet and outlet conduits to carry the gas through the water reservoir and gas chamber. The improvement comprises an audible pressure relief valve in association with the gas chamber. When a predetermined pressure within the gas chamber has been exceeded, the pressure relief valve opens to relieve the excess pressure and to simultaneously warn the operator than the predetermined pressure level has been exceeded. The alerted operator may then check to determine if there has been a malfunction in the apparatus or ancillary apparatus.

Abstract: The disclosure is of a captured nut coupling particularly adapted to join two articles and to convey fluids between the joined articles. The coupling is a fastener comprising a split ring inner or male member and a solid retaining and locking outer or female member. The male and female members are locked together after the male member is connected to one of the articles to be joined. In one embodiment the inner male member bears an inner rib which rotatably engages a groove in one of the articles for connection and the outer female member includes a means for engaging the other article for connection.

Abstract: The disclosure is of a ring type opener for removing the cap portion of a hermetically sealed molded plastic container having an integrally molded cap portion. The opener includes a means for engaging and holding the cap during and after removal, in a plane parallel to the normal axis of the container so that it will lift evenly and remain within the ring opener following severance.