Circulation Study

Circulation gets measured as a percentage and designed as what is left over between rooms. The questions that decide whether a building works are different: who is walking, where from, where to, and who do they meet on the way.

Workflow

Step 1. Name the journeys before looking at the plan

Ask, in one message:

1. Who moves through this building? List every group, including the ones that are not people: goods, waste, laundry, food, records, specimens, plant, money, prisoners, patients, animals, whatever this building has.
2. For each group: where do they arrive, where do they go, and what do they do on the way?
3. Which pairs must not meet, and what requires the separation?
4. What changes out of hours: doors locked, desks unstaffed, entrances closed?
5. What happens on the busiest day rather than the average one?

Question 1 is where studies fail. A plan that works for staff and visitors can be unworkable for waste, and waste is never on the list until somebody asks.

Step 2. Trace each journey, door by door

One table per journey, not a summary:

Step	From	To	Through	Doors	Depends on	Note

Depends on is the column that earns the study: a door that has to be unlocked, a desk that has to be staffed, a lift that has to be called, a sign that has to be read, somebody who has to be asked. A route depending on any of those is a route that fails at 7pm or on the first day.

Trace in both directions. Journeys are rarely symmetrical, and the return trip is where people get lost.

Step 3. Find the crossings

Lay the journeys over each other and report every place two share a space:

Journey A	Journey B	Where	Required separate?	What separates them

For each crossing that should not happen, say what would separate them: a different route, a time separation, a door, a lobby, or a change to the plan. Time separation is a legitimate answer and it is also an operational commitment, so name who owns it.

Report crossings that are fine as well as crossings that are not. A study that lists only problems does not show that the rest was looked at.

Step 4. Compare the journeys against each other

• Length and clarity by group. Which group has the longest or least obvious route, and is that the group least able to cope with it? A visitor route longer than the staff route is normal; a patient route longer than the staff route usually is not.
• Number of decisions. Count the points where someone has to choose a direction. That count, not corridor width, is what makes a building feel confusing.
• First-time versus daily. Trace one journey as somebody who has never been here. Every route that works only with familiarity is flagged.

Step 5. Report

The journeys, the crossings, the comparison, then:

• Every route depending on a person, a key or a sign, counted.
• Every required separation not achieved, listed individually with what requires it.
• Every journey that was named but not traced, and why.
• What was assumed about the operation rather than told.

Close by pointing at design-egress for the egress arithmetic and at the accessibility standard for the accessible route.

Step 6. Save, if asked

Ask whether to write the study to a file and where.

Rules

• Never supply a width, a distance, or a circulation percentage.
• Name the journeys before opening the plan, and include the non-human ones.
• Trace door by door, in both directions.
• Every route dependency on a person, key or sign is recorded.
• Report crossings that are acceptable as well as those that are not.
• Never present this as egress compliance or accessibility review.

Anti-patterns

• Measuring circulation as a percentage and calling it studied.
• Tracing only the routes the plan was designed around.
• Forgetting waste, goods, or anything that arrives at a back door.
• Tracing one direction and assuming the return is the same.
• Treating a time separation as achieved without naming who operates it.
• Calling a route clear because it is clear to someone who drew the plan.
• Doing the egress arithmetic here.

Resources

None. This skill is one file. Output is written directly at the path you choose.