In consultation with Siemens, users must decide whether the materials used for theVRD4xs are suitable for the intended types of recycling gas. These gases can vary interms of both their composition and the respective concentration of the components. Asa result, it is not possible to make any warranties or definitive statements regardingservice life. An assessment should be carried out to determine the suitability of the gasused.For safety reasons, we strongly recommend- the installation of a valve proving device- a visual inspection of the VRD4xs at intervals of 6 to 12 months- the use of SKPx5s with a valve closing contact