An arrangement has to
reach all the way out.
I found excellent toilets at head office. That was good for the people who worked there.
Then I found the cleaner on the evening round, the fitter at the customer’s site and the employee behind the shop counter. They needed solutions where they actually were.
Before a job: sort out toilets, water, waste and breaks. In a shop, someone must be able to cover. When travelling, necessary support must be obtainable. Working from home is one workplace among several.
Also test height, reach and operation. An arrangement can be hard to use with reduced hand strength, sight or mobility. Information must be understandable, also for new employees and people who speak another language.
That helps little if you are somewhere else.
Walk through an actual shift or customer job. Include part-time staff, agency workers and temps in the arrangements, and agree responsibility with the right employer or host. Nobody should have to give a diagnosis to find the toilet.