Abstract: Intermediate a first pressure reducing means (12, 15) reducing the pressure f a pressure source (10) to nearly the external pressure P.sub.A of the diving depth, and the respiratory mask (18) of the diver, there is a flexible first buffer container (16) whose internal pressure is slightly above the external pressure to ensure that a buffer volume of respiration gas is continuously available directly to the diver. A second buffer container (21) is mounted intermediate the respiratory mask (18) and a second pressure reducing means (26, 23) for waste air. The pressure maintained in the second buffer container is slightly below the external pressure P.sub.A so that a specific exhalation volume is permanently available to the diver. To avoid a direct blowing through the respiratory mask, a relief pressure valve (20) only opens responsive to the lung activity of the diver.

Abstract: A guy yoke for use in a guyed structure terminate two support guys coupled to said structure and to transfer loads entered on said supported guys to anchor means, said guy yokes includes two arms pivotally coupled to an anchor plate at one end and coupled to guy wires at the other end. A spreader arm is coupled to the arms to maintain them in a fixed position for forces transmitted by the guy lines which are below a predetermined level. The spreader arm is coupled to the two arms by shear bolts or pins. When the forces transmitted to the yoke are at or exceed the predetermined level, one or both of the shear bolts or pins is severed permitting the two arms to swing toward each other and thereby add effective length to the guying.