What’s on the Datums & Benchmarks poster
A definition and 6 facts worth remembering.
A datum is the agreed zero for height or position; a benchmark is a physical point whose value is known.
- A level without its datum is not information
- A site datum may be local and arbitrary
- Record the datum on every drawing issued
- Check a benchmark before you trust it
- Benchmarks move: settlement, works, damage
- Two independent checks beat one good one
- Common site convention — Datum set at 100.000 m
- Transfer to site — From two marks, not one
- Two contractors working to different datums build a step into the same slab.
Educational reference. Datum, projection and epoch must be recorded. National datums are defined by the mapping agency.
Questions about the Datums & Benchmarks poster
- What’s on the Datums & Benchmarks poster?
- A definition and 6 facts worth remembering. A datum is the agreed zero for height or position; a benchmark is a physical point whose value is known. A level without its datum is not information; A site datum may be local and arbitrary; Record the datum on every drawing issued; Check a benchmark before you trust it; Benchmarks move: settlement, works, damage; Two independent checks beat one good one; Common site convention — Datum set at 100.000 m; Transfer to site — From two marks, not one; Two contractors working to different datums build a step into the same slab.. Educational reference. Datum, projection and epoch must be recorded. National datums are defined by the mapping agency.
- Who is the Datums & Benchmarks poster for?
- Datums & Benchmarks belongs to the Civil Engineering section rather than to a school year, because engineering is not something one grade owns. Anyone learning surveying can pin it up — a beginner, a student mid-course, or someone revising years later.
- When should you use the Datums & Benchmarks poster?
- Starting work on a site, or reconciling two sets of drawings. A wall chart earns its place by being glanceable from where the work is happening, so Datums & Benchmarks belongs on the wall where that engineering work actually happens, within glancing distance, rather than filed away.
- What other posters go with Datums & Benchmarks?
- GNSS Surveying, Levelling and Areas & Volumes sit alongside Datums & Benchmarks in the Civil Engineering section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.GNSS SurveyingLevellingAreas & Volumes
- Is the Datums & Benchmarks poster free to download and print?
- Yes. Datums & Benchmarks downloads as a free PDF with no account, no email and no watermark, like everything else in the Civil Engineering section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
- What size does the Datums & Benchmarks poster print at?
- Datums & Benchmarks is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Datums & Benchmarks loses nothing.Printing guide
Related posters
Charts that sit alongside Datums & Benchmarks on the same wall.
Browse every Civil Engineering poster, or start from the full catalogue.