ASPRS Approves Edition 2 of the ASPRS Positional Accuracy Standards for Digital Geospatial Data

Baton Rouge, LA, September 12, 2023: The American Society for Photogrammetry and Remote Sensing (ASPRS) is pleased to announce approval of the Positional Accuracy Standards for Geospatial Data, Edition 2, Version 1.0, which includes Addendum I: General Best Practices and Guidelines and Addendum II: Best Practices and Guidelines for Field Surveying of Ground Control and Checkpoints. Modifications implemented in Edition 2 respond to evolving technologies and industry needs. The new edition was drafted by ASPRS subject matter experts representing public, private, and academic sectors. Public review was conducted from February 8 – April 30, 2023. Comments were incorporated into the final version adopted on August 23, 2023.

“The new edition of these standards will have a positive impact on our geospatial capabilities and all who benefit from these services here in the United States of America and worldwide for years to come, it is a historical moment that we should all be proud of,” said Dr. Qassim Abdullah, Vice President and Chief Scientist of Woolpert, who led the ASPRS Positional Accuracy Standards Working Group. “We are fortunate to have among our members such talented and willing volunteers who worked hard during the last two years to update this important Standard,” said Lorraine Amenda, ASPRS President.

As the USGS Lidar Base Specifications is well aligned with the ASPRS accuracy standards, users of the 3DEP program will reap the benefits from the modifications introduced in Edition 2. “As our 3DEP Lidar Base Specification is closely aligned with the ASPRS standards, we welcome these updates to the standards introduced in the Second Edition. We hope these updates bring even more clarity to an already well adopted standard on acquiring geospatial data,” said Dr. Michael Tischler, Director, USGS National Geospatial Program.

The most significant changes introduced in this 2nd Edition of the ASPRS Positional Accuracy Standards for Digital Geospatial Data include:

1. Elimination of references to the 95% confidence level as an accuracy measure.

2. Relaxation of the accuracy requirement for ground control and checkpoints.

3. Consideration of survey checkpoint accuracy when computing final product accuracy.

4. Removal of the pass/fail requirement for Vegetated Vertical Accuracy (VVA) for lidar data.

5. Increase the minimum number of checkpoints required for product accuracy assessment from twenty (20) to thirty (30).

6. Limiting the maximum number of checkpoints for accuracy assessment to 120 for large project.

7. Introduction of a new term, “three-dimensional positional accuracy."

8. Addition of Guidelines and Best Practices Addendums for:

a. General Guidelines and Best Practices

b. Field Surveying of Ground Control and Checkpoints

c. Mapping with Photogrammetry

d. Mapping with Lidar

e. Mapping with UAS

There are also three additional Addendums listed in the Table of Contents:

• Addendum III: Best Practices and Guidelines for Mapping with Photogrammetry

• Addendum IV: Best Practices and Guidelines for Mapping with Lidar

• Addendum V: Best Practices and Guidelines for Mapping with UAS

These three Addendums will be available for public comment in the coming weeks and will be added to Edition 2, Version 2.0, which ASPRS anticipates approving in late Fall 2023.

The significant changes in Edition 2 are summarized in the Foreword. To download the document, visit https://publicdocuments.asprs.org/PositionalAccuracyStd-Ed2-V1.

Established in 1934, the American Society for Photogrammetry and Remote Sensing (ASPRS) is a scientific association serving over 2,000 professional members around the world, providing its members professional development through education and networking experiences, professional certification, publications, scholarships, and other services. ASPRS advances the knowledge and improves understanding of mapping sciences to promote the responsible applications of photogrammetry, remote sensing, geographic information systems (GIS) and supporting technologies.