You have a case that claims the lighting was “bad”. Is it OK to look at the site and say “Yes, it is well lit” or “Gee, it’s very dark”? Or do you need to obtain lighting measurements? In this video, Dr Jennifer Long explains some of the complexities of measuring illuminance, and some of the factors to consider when briefing an expert to answer the question “Was there enough light?”
This is sometimes raised as an issue when people fall downstairs, trip upstairs, or trip on pavements.