Security Design Review

Security arrives late, as a schedule of cameras and card readers on a plan that was never asked the question. Almost everything that works is in the layout: who can see what, where the boundary is, and whether the building tells people where they are allowed to be without anybody having to enforce it.

Workflow

Step 1. Establish who is meant to be where, and when

Ask, in one message:

1. Who uses the building: public, staff, visitors, contractors, deliveries, children, patients, students, residents? Point at circulation-study.
2. Where is each group meant to be, and where not?
3. What is the client actually worried about? Theft, violence, a specific person, a specific asset, unauthorised access, or an incident that already happened?
4. What are the hours, and who is on site outside them?
5. Is there a policy, an operator's standard, or a regulator's requirement? Quote it.
6. Who staffs the boundary, if anyone, and at what times?

Question 6 is the one that decides whether the plan works. A layout that depends on somebody at a desk is a layout that fails at six o'clock, and most plans depend on one without saying so.

Step 2. Find where the boundary actually falls

The public-to-controlled boundary is drawn somewhere, and it is rarely where the plan implies:

Boundary	Where the plan puts it	Where it actually falls	What holds it

• What is the first controlled door, and what is in front of it?
• Can somebody reach the lift lobby, the stair, or the washrooms before being seen or stopped?
• Is there a place a visitor waits, and is it inside or outside the boundary?
• Where do deliveries cross, and does the goods route reach controlled space?
• Do the fire stairs discharge into controlled space, and does that create a way in? Egress wins over security here, always, and the answer is a design one.
• Does the boundary hold at every level, or only at the entrance?

A boundary held by one door on one floor is not a boundary. Report every place it is bypassed.

Step 3. Find where somebody can be unobserved

Natural surveillance is the part of this that is free, and it is a plan question:

• Which spaces are overlooked by ordinary use, and which are not?
• Where can somebody stand, wait, or work without being seen: behind a projection, in a recessed entrance, at the back of a car park, in a service yard, in an unstaffed corridor, in a stair?
• Are the routes people take at night the ones that are overlooked, or the short ones that are not?
• What is dark? Point at senior-lighting-consultant, and note that lighting a place nobody overlooks does not make it safer, it just makes it visible.
• Do the desks and rooms with people in them face the places that need watching, or away from them?

Step 4. Read the layout as a set of instructions

A building that tells people where they may go needs less enforcement:

• Is it obvious, without a sign, where the public may go and where they may not?
• Does the route to reception pass anything it should not?
• Are the controlled doors obviously controlled, or do they look like any other door?
• Is there a clear front, so that arriving anywhere else feels wrong?
• Where the plan relies on a sign, note it. Signs are what get used when the layout did not answer the question.

Step 5. Work the after-hours case, separately

Almost every plan works when staffed. Run the whole building again as if nobody is there:

• Which doors are locked, and what does that do to the routes people still take?
• Who is in the building alone, and how do they get to their car?
• What is accessible from outside: a roof reachable from a wall, a service yard, a window over a canopy, an unlocked stair?
• What does a cleaner's or a contractor's access look like, and does it defeat the boundary?
• Does locking anything compromise egress? If so it is not an option, and the answer has to be a design one.

Step 6. Report

• Where the boundary actually falls, and every place it is bypassed.
• Every unobserved place, with what would resolve it in the layout.
• Every point where the plan depends on a person, and what happens when they are not there.
• The after-hours findings, separately.
• What is left for equipment, and what equipment cannot fix.
• Any conflict between security and egress, named for the code consultant.

Close by saying no threat assessment was made and no system was designed.

Step 7. Save, if asked

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

Rules

• Ask who staffs the boundary and when, every run.
• Work the layout before naming any equipment.
• Report every place the boundary is bypassed, not only where it holds.
• Run the whole building again for the after-hours case.
• Egress wins over security. Name every conflict for the code consultant and never propose locking an exit.
• Note every place the plan relies on a sign.
• Never assess threat or specify a system.

Anti-patterns

• Answering with a camera and a card reader schedule.
• Assuming a reception desk is staffed at all times.
• Lighting a place nobody overlooks and calling it safer.
• A boundary held on the ground floor and open on every other.
• Ignoring the fire stair as a way in.
• Reviewing the staffed case only.
• Proposing anything that locks an exit.
• Relying on signage where the layout could have answered it.

Resources

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