Pressure container A1. What does it mean to have a single layer?
The pressure vessel A1 is the super high pressure vessel and the high pressure vessel. The high pressure vessel should note the structural form of single, multi-layer, welding, coiling and hot sets. So the pressure vessel A1 that you're asking is that the pressure vessel should be confined to a single layer of structure.
You can only make single-layer pressure vessels, you can't make multi-layer pressure vessels.
The A1 aptitude includes single-layer containers and multi-layer packing containers. If you only have a single layer of manufacturing license, you can only make single-layer containers, and you can't manufacture multiple layers of packing containers.
