Element Level Bridge Inspection MBEI and Condition State Coding
By Grace on June 18, 2026
Element-level bridge inspection has replaced the traditional deck-superstructure-substructure rating system as the standard for bridge condition assessment under the NBIS and SNBI framework. The AASHTO Manual for Bridge Element Inspection defines a standardized element catalog, four-condition-state coding system, and inspection workflow that every state DOT and bridge agency must now follow. For inspectors transitioning from component-level ratings to element-level coding, understanding the MBEI element catalog, condition state definitions, defect tracking, and SNBI reporting requirements is the difference between compliant data and rejected submittals.
MBEI Element Catalog · Four Condition States · NBE and BME Coding · SNBI Reporting
Element-Level Bridge Inspection Is the New Standard. Master the MBEI Catalog, Condition State Coding, and SNBI Element Reporting Workflow.
iFactory helps state DOTs and bridge agencies implement element-level inspection workflows, validate condition state coding against AASHTO MBEI standards, and prepare element data for SNBI-compliant submittals.
Standard condition states per element — Good, Fair, Poor, Severe — applied consistently across all NBE and BME categories.
800+
Agency-Defined Element identification numbers reserved for state-specific sub-elements and custom inspection categories.
2
Element types defined in the MBEI: National Bridge Elements for primary components and Bridge Management Elements for secondary systems.
3
Units of measure used across all elements: length in feet, area in square feet, and each for enumerated components.
What Element-Level Bridge Inspection Replaces and Why It Matters
The previous bridge inspection standard relied on component-level ratings: a single numeric code for deck condition, a single code for superstructure, and a single code for substructure. These three ratings could not capture the reality that different parts of the same component deteriorate at different rates. A steel girder bridge might have span one with section loss and pack rust while span two is in good condition — under component-level ratings, the superstructure received a single compromised rating that obscured the actual distribution of deterioration.
Element-level inspection solves this by breaking each component into individual elements — discrete structural or functional members with their own quantity, unit of measure, and condition state assignment. A deck becomes multiple elements: the concrete deck itself, the wearing surface, the joints, the protective system. Each element is assigned four condition state quantities that sum to the total element quantity, giving bridge owners an accurate, granular picture of condition distribution across every part of the structure. This granularity is what makes deterioration forecasting, preservation planning, and performance measurement possible at the network level.
Component-Level vs Element-Level Inspection — What Changes in Practice
Condition Rating
Single Code per Component vs Quantities per Condition State
Component-level used a single 0-9 rating for each of three components. Element-level assigns four condition state quantities (CS1 through CS4) to each element, where the sum of all four states equals the total element quantity. An inspector records, for example, that of 1,200 sq ft of concrete deck, 800 sq ft is in CS1, 300 sq ft in CS2, 100 sq ft in CS3, and 0 sq ft in CS4 — capturing the exact distribution of deterioration rather than a single average code.
Coding impact: Condition state quantities must sum to the total element quantity. Rounding rules apply from CS4 upward.
Element Granularity
Three Components vs Hundreds of Element Types
The Coding Guide defined three rated components plus culverts. The AASHTO MBEI defines hundreds of element types organized in a master location matrix, grouped by major bridge assembly, element type, and material. Each element has a unique identification number, standard unit of measure, and four predefined condition states with specific defect descriptions. Elements span decks, slabs, girders, bearings, abutments, piers, culverts, railings, joints, protective coatings, and smart flags for special conditions like fatigue details.
Granularity impact: Element-level data enables precise deterioration modeling, preservation cost optimization, and network-level performance measurement.
Data Utilization
Federal Reporting Only vs Bridge Management Integration
Component-level ratings were designed primarily for FHWA reporting to Congress on overall bridge conditions. Element-level data serves both federal reporting and agency bridge management functions. AASHTOWare BrM, Pontis, and other bridge management systems use element-level condition data for deterioration curve development, life-cycle cost analysis, preservation scenario modeling, and project prioritization. The same data that satisfies SNBI reporting requirements directly feeds the agency's internal bridge management decisions.
Utilization impact: Element data is the foundation for TAMP development, performance target setting, and NHS bridge condition reporting under 23 USC 144.
AASHTO MBEI Compliance
Not Sure If Your Element Condition State Quantities Pass SNBI Validation?
iFactory validates element-level bridge inspection data against AASHTO MBEI standards — checking condition state quantity sums, element parent relationships, and defect coding consistency before SNBI submittal.
The AASHTO MBEI Element Catalog: NBE, BME, and ADE Classification
The Manual for Bridge Element Inspection organizes elements into two primary categories — National Bridge Elements and Bridge Management Elements — plus Agency-Defined Elements. Understanding which category an element belongs to determines whether it is reportable to FHWA, how condition states are applied, and what aggregation rules apply for SNBI submittal.
Category 01
National Bridge Elements
NBEs represent the primary structural components of bridges necessary to determine the overall condition and safety of primary load-carrying members. They refine the deck, superstructure, substructure, and culvert condition ratings from the Coding Guide. Examples include Element 12 Reinforced Concrete Deck, Element 107 Steel Open Girder/Beam, Element 205 Reinforced Concrete Column, Element 215 Reinforced Concrete Abutment, and Element 240 Steel Pier Cap. NBEs are mandatory for reporting on NHS bridges. Condition state language is standardized and consistent across all agencies reporting NBEs to FHWA.
Category 02
Bridge Management Elements
BMEs define secondary bridge components that support bridge management and preservation needs assessment. Examples include Element 510 Wearing Surface, Element 515 Steel Protective Coating, and Element 520 Concrete Protective Coating. BMEs have four condition states following the good, fair, poor, severe convention, but FHWA allows agencies some flexibility in condition state language for BMEs as long as the four states still represent the good through severe progression. Not all BMEs are reportable to FHWA; the SNBI identifies which BMEs must be included in the NBI submittal.
Category 03
Agency-Defined Elements
ADEs use element numbers 800 and above, reserved exclusively for agency purposes. They fall into three subcategories: subsets of NBEs (splitting a standard NBE into sub-elements for detailed tracking), subsets of BMEs, and independent ADEs with no tie to standard elements. ADEs that are subsets of NBEs or BMEs must be rolled back up (aggregated) into the parent NBE or BME for FHWA reporting. Independent ADEs are not submitted to FHWA. The condition state framework remains four states for all ADE categories.
The Four Condition States: CS1 Through CS4 Coding Rules
Every element in the AASHTO MBEI has exactly four condition states. This is a fixed requirement — no element uses three, five, or a variable number of states. The condition states follow a consistent severity progression across all element types, material types, and defect categories. Understanding the general intent of each condition state and how defect-specific criteria modify the general descriptions is essential for accurate coding.
Condition State Definitions — General Descriptions and Defect Criteria
CS1 Good
The element is in sound condition with no significant defects. Any deterioration or distress is minor and does not require corrective action. The protective systems are functioning as intended. No structural review is needed.
No action required beyond routine maintenance
CS2 Fair
The element shows moderate deterioration or distress. Section loss, cracking, delamination, or other defects are present but do not compromise the strength or serviceability of the element. Protective systems may be beginning to fail. Corrective action is typically warranted but not urgent.
Corrective action recommended; plan within inspection cycle
CS3 Poor
The element has advanced deterioration or distress that affects its strength or serviceability. Section loss, cracking, or other defects are significant. The condition may warrant a structural review to determine the effect on the element or bridge. Corrective action is needed to prevent further deterioration or to restore serviceability.
The condition warrants a structural review to determine the effect on strength or serviceability of the element or bridge, or a structural review has been completed and the defects impact strength or serviceability. The element is in a condition that requires immediate attention. For primary load-carrying elements, CS4 indicates the condition has been evaluated and confirmed to affect structural capacity.
The single most common error we see in element-level bridge inspection data is condition state quantities that do not sum to the total element quantity. Inspectors transitioning from component-level ratings are used to assigning a single condition code per component. Element-level coding requires distributing the entire element quantity across four condition states, with the total of CS1 through CS4 equaling the element total exactly. This seems simple, but when you have multiple defects on the same element, the quantity distribution becomes a judgment call that depends on the severity and extent of each defect. The MBEI defect tables give specific guidance, but it takes practice and consistent training to get it right.
— Bridge Inspection Program Manager, State DOT — 8,500-Bridge Inventory
Element Coding Workflow: From Field Inspection to SNBI Submittal
The element-level inspection process follows a structured workflow that starts with element identification in the field and ends with SNBI-compliant data submission through NBI NextGen. Each step depends on the one before it, and errors at any stage cascade through the entire reporting pipeline.
Element Inspection Workflow — From Field to FHWA Submittal
Step 1
Element Identification & Quantity Measurement
Identify all applicable NBEs and BMEs for the bridge from the MBEI element catalog. Measure or calculate the total quantity of each element in its standard unit of measure — length in feet, area in square feet, or each for enumerated elements. Record the element number, parent number if applicable, and total quantity.
Step 2
Condition State Assessment
Inspect each element for all applicable defects defined in the MBEI. For each element, determine the quantity in each of the four condition states based on the severity and extent of defects. The sum of CS1 through CS4 must equal the total element quantity exactly. Use defect-specific criteria from the MBEI to differentiate between CS2 and CS3.
Step 3
Defect Recording & Data Quality Check
Optionally record specific defect quantities for elements in CS2 or lower. Validate that condition state quantities sum correctly, element parent relationships are consistent, and all required NHS bridge elements are included. Verify that ADE sub-elements are properly aggregated into their parent NBE or BME for federal reporting.
Step 4
SNBI Data Submittal via NBI NextGen
Package element identification and condition data in the SNBI JSON submittal schema. Each element record includes BE01 (Element Number), BE02 (Parent Number), BE03 (Total Quantity), and BCS01-BCS04 (Condition State Quantities). Submit through NBI NextGen validation module and resolve any critical or error-level validation findings.
SNBI Element Reporting: How MBEI Data Maps to the Federal Submittal Schema
The SNBI incorporates element-level data directly into the main NBI submittal, ending the era of separate inventory and element data files. Element identification is reported under Subsection 7.2 and element conditions under Subsection 7.3 of the SNBI. For every element inventoried on an NHS bridge, the submittal must include the element number, total quantity, and the quantity in each of the four condition states. These element data items are reported as multiple records per bridge, with each element record linked to the bridge through the state code and structure number.
SNBI Element Data Items — Subsection 7.2 and 7.3 Field Mapping
B.E.01 Element Number
Numeric code identifying the element type from the AASHTO MBEI catalog. Examples: 12 for reinforced concrete deck, 107 for steel open girder/beam, 205 for reinforced concrete column, 215 for reinforced concrete abutment. Each distinct element on the bridge receives its own element record with the appropriate element number.
B.E.02 Element Parent Number
Reported when the element is a child of a parent element. Used for smart flags and sub-elements that relate to a specific parent. For example, a smart flag for fatigue-sensitive details is reported as a separate element record with the parent element number of the steel girder it applies to. Not required for all element records.
B.CS.01 – B.CS.04 Condition State Quantities
Four numeric fields reporting the element quantity in each condition state. The unit of measure is the element's standard unit (feet, square feet, or each). The sum of all four condition state quantities must equal B.E.03 Total Quantity. Quantities are reported as whole numbers using rounding rules that prioritize CS4 through CS1.
Conclusion
Element-level bridge inspection is not an optional enhancement to the component-level system — it is the federally required standard under the NBIS final rule and the SNBI. Every state DOT and agency performing bridge inspections on NHS bridges must collect element-level data using the AASHTO MBEI catalog, assign four condition state quantities per element, and report the data through the SNBI submittal schema. The transition from component-level to element-level coding requires training, practice, and consistent quality control — but the payoff is a bridge condition picture that supports accurate deterioration modeling, preservation optimization, and network-level performance management.
Agencies that invest in element-level inspection quality — consistent condition state assignment, accurate quantity measurement, proper defect recording, and reliable ADE aggregation — will produce SNBI submittals that pass NBI NextGen validation on the first attempt and provide bridge management data their agencies can actually use for decision-making. Agencies that treat element-level coding as a compliance exercise without investing in inspector training and data quality processes will face repeated validation errors, rejected submittals, and bridge management data that cannot support meaningful analysis.
iFactory helps state DOT bridge programs implement element-level inspection workflows, validate condition state coding against AASHTO MBEI standards, and prepare element data for SNBI-compliant submittals. Book a Demo to see how our platform supports element-level inspection data quality and SNBI reporting, or talk to an expert about an element inspection program assessment for your agency.
Frequently Asked Questions
Component-level inspection assigns a single 0-9 condition rating to each of three components: deck, superstructure, and substructure. Element-level inspection breaks each component into individual structural elements, each with its own quantity and four condition state quantities (CS1 Good through CS4 Severe). For example, instead of one deck rating, an element-level inspection records quantities of concrete deck in each condition state, plus separate quantities for joints, wearing surface, and protective coatings. Element-level data supports deterioration modeling, preservation planning, and performance measurement that component-level ratings cannot provide. Talk to an expert about transitioning your agency from component-level to element-level inspection.
Under 23 USC 144, all bridges on the National Highway System require element-level data collection and reporting to FHWA. This mandate has been in effect since April 2015. Many states also collect element-level data for non-NHS bridges as part of their bridge management programs. The SNBI requires element identification and condition data for all NHS bridges in the NBI submittal. Element data includes element number, parent number, total quantity, and quantities in each of the four condition states. The element identification dataset is mandatory for NHS bridges, and the NBI NextGen validation module checks for its presence. Book a Demo to see iFactory's element-level inspection workflow.
When multiple defects exist on the same element, the inspector must assess the combined effect of all defects to determine the condition state for each portion of the element quantity. The governing condition state is driven by the most severe defect present on that portion of the element. The MBEI provides defect-specific condition state criteria for each element. Defect recording is optional but recommended — when defects are recorded, the element condition must be inclusive of all defined defects. The sum of CS1 through CS4 quantities must always equal the total element quantity, regardless of how many defects are present. Talk to an expert for guidance on defect-based condition state assignment.
Smart flags are special element types used to report conditions that affect specific bridge elements but are not themselves physical elements. Examples include Element 358 Fatigue-Sensitive Steel Detail, Element 359 Pack Rust, Element 360 Corrosion, and Element 361 Section Loss. Smart flags are reported as element records with their own element number, parent element number (linking to the affected element), total quantity, and condition state quantities. They enable inspectors to document specific deterioration mechanisms that might otherwise be lost in a general condition rating. Smart flags follow the same four-condition-state framework as all other elements. Book a Demo to see how iFactory handles smart flag coding and reporting.
Agency-Defined Elements use element numbers 800 and above and fall into three categories: subsets of NBEs, subsets of BMEs, and independent ADEs. ADE subsets of NBEs or BMEs must be aggregated back into the parent NBE or BME before FHWA submission — they are not reported independently to FHWA. Independent ADEs are not reported to FHWA at all. ADEs follow the same four-condition-state framework. Many agencies use ADEs to capture state-specific components such as unique pier types, proprietary expansion joints, or specialized protective systems that the standard element catalog does not cover. Talk to an expert about ADE management and aggregation for SNBI compliance.
The 2025 interim revisions to the AASHTO MBEI 2nd Edition became effective in April 2025 and include new National Bridge Elements for concrete anchorage blocks, steel and concrete anchorage chamber walls, steel primary cable saddles, and reinforced concrete pier towers. New Bridge Management Elements cover cable protective systems, vibration dampers, substructure impact protection, and steel primary cable bands. New defect elements for deck drainage systems and post-tensioning assemblies were also added. The revisions updated Section 2 (Element Location Matrix), Section 3 (Detailed Element Descriptions), and Appendix C (Element Groupings). Agencies must implement the 2022, 2024, and 2025 interims to have the complete current specification. Book a Demo to see how iFactory stays current with MBEI interim revisions.
Validate Your Element-Level Inspection Data Against AASHTO MBEI Standards and SNBI Schema Requirements.
iFactory helps state DOTs and bridge agencies implement element-level bridge inspection workflows, validate condition state coding, manage ADE aggregation, and produce SNBI-compliant element data submittals purpose-built for the NBI NextGen system.
