Guides for drawing traffic accident diagrams
Practical guides and worked examples for drawing clear collision diagrams: what to include, how to measure the scene and the mistakes to avoid.
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How to draw a traffic accident diagram, step by step
A practical walkthrough for drawing a clear traffic accident diagram: road layout, vehicle positions, directions of travel, point of impact and measurements.
Read article →What to include in an accident diagram: a practical checklist
The elements every accident diagram needs — vehicles, directions, impact point, traffic controls, measurements and identification — and what to leave out.
Read article →How to measure an accident scene for your diagram
Simple field techniques for measuring an accident scene — reference points, triangulation basics, what to measure first — and how to record distances on a diagram.
Read article →How to show vehicle direction of travel in an accident diagram
Direction of travel helps explain the sequence of a collision. How to draw travel arrows, pre-impact paths and intended maneuvers so a diagram tells a clear story.
Read article →Intersection accident diagram: a worked example
A worked example of an intersection collision diagram — failure to yield on a left turn — showing vehicle placement, arrows, impact point and measurements.
Read article →Parking lot accident diagram: a worked example
A worked example of a parking lot collision diagram — a back-out strike in an angled lot — with stall geometry, vehicle angles and the aisle context that matters.
Read article →Rear-end collision diagram: a worked example
How to diagram a rear-end collision so it shows more than 'one car behind another': following distance, braking evidence, stopped traffic and impact alignment.
Read article →Seven common mistakes in traffic accident diagrams
The mistakes that make accident diagrams confusing or unusable — from missing direction arrows to invented precision — and how to avoid each one.
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