Updated bridge inspection standards include use of drones

June 7, 2022

Tyson Fisher


A new Federal Highway Administration rule updating the National Bridge Inspection Standards is now in effect.

On Monday, June 6, a final rule submitted by FHWA addressing bridge inspections is official. The National Bridge Inspection Standards were last updated more than a decade ago.

According to the final rule published in the Federal Register, The Moving Ahead for Progress in the 21st Century Act (MAP-21) requires the U.S. Department of Transportation to update the National Bridge Inspection Standards. Provisions within MAP-21 include new requirements for:

  • The highway bridge inspection program.
  • Maintaining a bridge inventory.
  • Reporting to FHWA the inspection results and critical findings (“critical findings” include any structural or safety-related deficiencies that require immediate follow-up inspection or action).

New rules include “options for more rigorous, risk-based intervals based on the consideration of certain factors,” including an inspection interval tolerance of three months beyond the inspection date. Specific criteria allow for extended routine inspection intervals up to 48 months, and 72 months for underwater inspections.

Additionally, the new National Bridge Inspection Standards include the use of unmanned aircraft systems, commonly known as drones.

Rules last updated in 2009 make no mention of the latest advances in technology. However, new rules addressing drones are ambiguous and will likely be clarified in a future update.

“FHWA has been researching opportunities for the appropriate use of (drones) in the bridge inspection program and monitoring the research of others,” FHWA states in its final rule document. “FHWA will continue to look for opportunities and integrate these tools when it is believed they will contribute to the continued success of the bridge inspection program.”

The updated National Bridge Inspection Standards apply to all structures defined as highway bridges on all public roads, on and off federal-aid highways. That includes tribally and federally owned bridges. Inspection standards also apply to private bridges that connect to a public road on each end. LL