From NAICS to Hazard Group: How InsightUW Maps External Industry Codes to Internal Actuarial Classes
How InsightUW transforms a 6-digit NAICS code into a rate-ready hazard group and factor — through a deterministic, LOB-aware mapping chain that bridges government classification standards and carrier-specific actuarial tables.
The Problem
External industry classification systems were not designed for insurance rating. NAICS codes organize the economy into 1,057 industries for census and trade purposes. SIC codes do the same for SEC reporting. Neither tells an underwriter what hazard group applies, what rate factor to use, or how the classification differs between General Liability and Workers Compensation.
Carriers bridge this gap with internal actuarial classification tables — but these tables live in spreadsheets, rating manuals, and tribal knowledge. When a new underwriter classifies "NAICS 236220 - Commercial and Institutional Building Construction," they may assign it to a different internal class than a senior underwriter would. Multiply that inconsistency across 500 submissions per month, and portfolio analytics become unreliable.
The mapping problem is also LOB-dependent. The same NAICS code can map to entirely different hazard groups depending on the line of business. A construction company rated for Workers Comp faces a different risk profile than the same company rated for General Liability.
The InsightUW Approach
InsightUW maintains a centralized actuarial class mapping table (Actuarial Class Map) that defines the complete chain from external industry code to internal rate factor. The mapping is deterministic, LOB-aware, and auditable.
The Mapping Chain
The complete chain from external code to rate factor follows six deterministic steps:
| Step | From | To | Example |
|---|---|---|---|
| 1 | NAICS 236220 | SIC 1522 | Government code cross-reference |
| 2 | SIC 1522 + LOB: WC | CN-BLD-01 | LOB-aware internal class lookup |
| 3 | CN-BLD-01 | Construction - Heavy | Actuarial segment assignment |
| 4 | Construction - Heavy | Hazard Group IV | Segment-to-hazard mapping |
| 5 | Hazard Group IV | Rate Factor 1.80x | Hazard-to-factor table |
| 6 | CN-BLD-01 + LOB: WC | NCCI WC 5403 | Regulatory class code |
Hazard Groups and Rate Factors
InsightUW defines four hazard groups aligned with industry-standard actuarial practice:
| Hazard Group | Description | Rate Factor | Example Industries |
|---|---|---|---|
| I | Low hazard | 0.65x | Financial services, professional services, technology |
| II | Moderate hazard | 1.20x | Retail, food service, light manufacturing |
| III | Elevated hazard | 1.50x | Transportation, warehousing, healthcare |
| IV | High hazard | 1.90x | Heavy construction, mining, chemical manufacturing |
Rate factors are multipliers applied to base premium during the rating step. A Hazard IV classification at 1.90x means the base premium is nearly doubled to reflect the elevated loss exposure.
The Actuarial Class Map Table
The mapping table ships with 18 LOB-aware records covering the most common commercial insurance classifications:
| Internal Class | Description | NAICS | SIC | Hazard | Factor | ISO GL | NCCI WC |
|---|---|---|---|---|---|---|---|
| CN-BLD-01 | Construction - Heavy | 236220 | 1522 | IV | 1.90 | 91580 | 5403 |
| CN-RES-01 | Construction - Residential | 236115 | 1521 | III | 1.50 | 91340 | 5645 |
| FI-BNK-01 | Financial - Banking | 522110 | 6022 | I | 0.65 | 61226 | 8810 |
| FI-PAY-01 | Financial - Payments | 522320 | 6099 | I | 0.85 | 61227 | 8810 |
| HC-PHY-01 | Healthcare - Physician | 621111 | 8011 | II | 1.20 | 64074 | 8832 |
| HC-HOS-01 | Healthcare - Hospital | 622110 | 8062 | III | 1.50 | 64075 | 8833 |
| FS-RES-01 | Food Service - Restaurant | 722511 | 5812 | II | 1.20 | 16910 | 9082 |
| TK-SFT-01 | Technology - Software | 511210 | 7372 | I | 0.65 | 41677 | 8810 |
| EN-RNW-01 | Energy - Renewable | 221114 | 4911 | II | 1.20 | 49451 | 7539 |
LOB-Aware Mapping
The same NAICS code maps differently depending on the line of business. This is critical for accurate rating:
| NAICS | Company Type | GL Mapping | WC Mapping |
|---|---|---|---|
| 236220 | Heavy Construction | ISO GL 91580, Hazard III, 1.50x | NCCI WC 5403, Hazard IV, 1.90x |
| 622110 | Hospital System | ISO GL 64075, Hazard II, 1.20x | NCCI WC 8833, Hazard III, 1.50x |
| 722511 | Restaurant Chain | ISO GL 16910, Hazard II, 1.20x | NCCI WC 9082, Hazard II, 1.20x |
Workers Comp classifications are typically more severe because they reflect bodily injury exposure to employees, while GL classifications reflect third-party liability. InsightUW captures this distinction in the mapping table so the correct hazard group is applied automatically based on the submission's LOB.
Extending the Mapping Table
Administrators add new mappings through the Reference Data admin interface:
- Navigate to Admin > Reference Data > Actuarial Class Maps
- Click Add Mapping
- Enter NAICS, SIC, internal class code, LOB, hazard group, rate factor, ISO GL code, NCCI WC code
- Save — the mapping is immediately available for new classifications
No code deployment is required. The mapping table is data-driven and extensible.
Workers Compensation: Ironclad Construction
A broker submits a Workers Comp application for "Ironclad Construction," a heavy civil engineering firm. The D&B lookup (Blog 36) has already resolved the company and returned NAICS 236220.
| Chain Step | Value | Source |
|---|---|---|
| NAICS | 236220 (Commercial Building Construction) | D&B lookup |
| SIC | 1522 (General Contractors - Nonresidential) | NAICS-SIC cross-reference |
| Internal Class | CN-BLD-01 (Construction - Heavy) | Actuarial Class Map, LOB=WC |
| Actuarial Segment | Construction | Class-to-segment mapping |
| Hazard Group | IV | Segment-to-hazard mapping |
| Rate Factor | 1.80x | Hazard-to-factor table |
| NCCI WC Code | 5403 | Regulatory class code |
| ISO GL Code | 91580 | Cross-reference (for multi-LOB) |
Impact on premium: The base WC premium for a company with 8,500 employees and $2.1B payroll is significant. A Hazard IV classification at 1.80x versus a misclassified Hazard II at 1.20x represents a 50% premium difference — potentially hundreds of thousands of dollars.
What the underwriter sees: The classification chain is displayed as a visual panel on the submission detail page. Each node in the chain (NAICS, SIC, internal class, hazard group, rate factor) is clickable, showing the source record and mapping rule that produced it.
What This Means for Underwriters
- Deterministic classification — Every NAICS code maps to exactly one internal class, hazard group, and rate factor for a given LOB, eliminating subjective interpretation
- LOB-aware accuracy — The same company is classified differently for GL versus WC, reflecting the actual risk profile for each line of business
- Regulatory compliance — ISO GL and NCCI WC class codes are auto-populated, reducing errors in statutory filings and bureau reporting
- Transparent mapping — The full chain from NAICS to rate factor is visible and auditable, so underwriters can verify and override any step
- Data-driven extensibility — New industry mappings are added through the admin interface without code changes, allowing the actuarial team to maintain classifications directly
What's Next
The mapping table converts a single NAICS code into a rate-ready classification — but how does InsightUW orchestrate the full journey from D&B lookup through actuarial mapping to confidence scoring? Blog 38 covers the 6-step auto-classification pipeline that ties every component together.
InsightUW is an AI-powered underwriting workstation for P&C carriers. Request a demo to see actuarial class mapping in action.