If you would like to work as an expert in the field of high-pressure gas pipelines, you must be recognized as an expert by the responsible body.
If you want to build or operate a filling system for filling compressed gases into portable pressure devices with a filling capacity of more than 10 kg/h or make certain safety-relevant changes to the design or operating method, you need a permit.
If you want to clean a facade with a high-pressure cleaner, you must report this.