A technical checklist for outsourcing LiDAR production

Describe the source and reference systems

Provide a data inventory and representative files. Record what is known about capture date, sensor, registration, coverage and source limitations. A missing vertical reference or a unit mismatch can affect an entire delivery, so resolve these before production.

• Area of interest, file inventory, tile scheme and naming convention.
• Horizontal CRS, vertical datum, geoid model and units; identify any requested transformation.
• LAS version, point data record format, extra attributes and required output compression.
• Coverage gaps, strip mismatch, variable density, occlusion and any acquisition QC report.

Specify classes and flags separately

List the required point classes with accepted examples for bridges, culverts, water, noise, vegetation and ambiguous structures. State flag rules for the selected LAS version and point record format. Do not assume an overlap class and an overlap flag are interchangeable.

• Clarify whether existing classes are retained, reviewed or replaced.
• Define custom class codes and which downstream software must read them.
• Agree how uncertain areas and withheld points will be recorded.

Reference: ASPRS LAS 1.4 R15 — classification and point-format definitions ↗︎

Scope terrain products as separate outputs

Classification alone does not define a terrain model. Specify raster resolution, grid alignment, interpolation, eligible point classes, bridge treatment, water treatment, voids and boundaries. Record breakline requirements and edge checks. Hydro-flattening is a surface treatment; a drainage or hydraulic model may need additional, separately specified work.

• Define whether each surface represents bare earth or top-of-surface features.
• Agree NoData treatment and how unsupported areas are delivered.
• Request the source breaklines and processing notes when they are part of the contract.

Reference: USGS Lidar Base Specification — DEM surface treatments ↗︎

Separate accuracy from production checks

File validity, class review and tile-edge inspection do not establish absolute positional accuracy. Define the accuracy assessment, reference observations and reporting method separately. Under the USGS Lidar Base Specification, checkpoints are independent of acquisition calibration control. If suitable reference data is absent, identify accuracy as unassessed rather than infer it from appearance.

• For each check, state the requirement, method, coverage or sample, tolerance and result format.
• Record who supplies and verifies independent reference observations.
• Keep acquisition limitations separate from defects introduced during processing.

Reference: USGS processing and positional accuracy requirements ↗︎

Agree access and acceptance before transfer

Start with a non-sensitive scope summary. Confirm the permitted storage and processing locations, authorized personnel, transfer method, retention period and deletion arrangements before sharing restricted data. In the commercial scope, define the review window, included corrections and treatment of new requirements.

• Name the client acceptance role and escalation contact in the project agreement.
• Request a manifest, reference-system notes, check summary and issue register.
• Require revised files to identify the version they replace.
• Use the pilot decision to approve production, revise the scope or stop.

Put the checklist to work

Use the editable templates to record your project requirements and delivery review. Adapt them to the applicable contract and specification.

• Download project scope checklist ↓
• Download delivery review template ↓