How do I mark an asset out of service?

Open Maintenance and press Sites and assets.
Press the asset to open it, then Tag out of service.
Say why, for example isolated at the valve, and press Tag it out. Its chip reads Tagged out.
Once it is fixed, open it again and press Back in service.

Worth knowing

Its failed test stays on its History. Tagging out records it in YourCA only: any tag on the asset itself is yours to fit.