Trucks at the site entrance

A line is traced on the ground of the way through, right where the barrier is, and it is given a direction: whatever crosses it inwards is an entry and whatever crosses it outwards is an exit. Two areas are painted on top: the internal track where trucks wait their turn, and the stretch of street in front of the gate, which is where you see whether the queue is spilling out of the site. Counting is not asked for out loud. Natural language is for searching and for describing a situation; a line cannot be described in a sentence, it has to be traced, because the figure depends on exactly where it runs and in which direction. That is why counting is set up by drawing, and that is why the figure is repeatable and can be audited: it is traced once and stays there, so this week's number and next month's can genuinely be compared.

A truck standing at the gate costs money from the first minute, and a concrete mixer waiting costs more still, because concrete works to its own clock and waits for nobody. Today the production manager knows the entrance jams first thing in the morning, but not by how much, nor on which days, nor whether it is the deliveries or the spoil going out. With the line and the two areas in place he has the figure: how many vehicles come in and go out each hour, how long they wait at the gate and when the queue spills onto the street. That is what it takes to move unloading slots and spread deliveries across the day instead of piling them all up at seven. And when the council or the neighbours ask about the traffic the site generates, there is a series to show instead of an impression. The figures on the illustration are an example, not any site's measurement.