Blue Diamond Industries (BDI) is a certified manufacturer of UL-listed High-Density Polyethylene (HDPE) conduit, specifically engineered for the rigors of power utility and electrical infrastructure. Our manufacturing processes and testing protocols ensure full compliance with Underwriters Laboratories (UL) safety standards.

Regulatory Compliance & Standards

BDI’s UL-listed duct is produced and tested to meet the following industry specifications:

• UL 651A: Standard for Type EB and A Rigid PVC Conduit and HDPE Conduit.
• UL 1990: Standard for Nonmetallic Underground Conduit with Conductors (Cable-in-Conduit).
• NEC Article 353: BDI UL-listed HDPE is fully compliant with the National Electrical Code (NFPA 70) for underground installations.

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Available Wall Thicknesses & Dimensions

We offer a variety of wall types to suit specific project depth and pressure requirements:

Performance in the Field

BDI’s UL-listed conduit is engineered with a high tensile strength-to-weight ratio and superior crush resistance. Combined with a low coefficient of friction, these features make our conduit the preferred choice for:

• Horizontal Directional Drilling (HDD)
• Plowing & Trenching
• Utility-Scale Power Distribution

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Engineering Insights: Navigating Wall Thickness

Choosing Between SDR 11 and UL Specifications:
Engineers often specify an SDR 11 wall thickness for demanding directional drilling; however, UL does not recognize SDR 11 in its current specifications.

• For diameters 3/4” through 4”: If you require a robust wall for tough field conditions, BDI recommends specifying UL EPEC-80 (Schedule 80). Its dimensions closely align with SDR 11 through these sizes.
  
• For diameters above 4”: SDR 13.5 (EPEC-B) is the heaviest UL-recognized wall available.

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Important Technical Notes:

• Smoothwall Only: In accordance with UL standards, UL-listed conduit is produced exclusively with a smooth inner wall; it is not available in a ribbed configuration.
  
• Certification Verification: NEMA TC7 conduit is not automatically UL certified. To ensure compliance, conduit must be produced and tested specifically to UL 651A or UL 1990 standards. While NEMA TC7 aligns with ASTM F2160, UL certification requires separate, rigorous testing protocols.

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Technical Resources:
Ensure your project submittals are accurate.

Don’t risk code violations with non-listed products. Our UL-Listed Technical Suite provides the exact submittals, NEC Article 353 guidelines, and Manufacturer Certifications required for a 100% compliant power installation.
 

Navigating the gap between SDR 11 performance and UL 651A requirements can be complex. Access our Technical Bulletin #2026-01 to see how our UL-Listed EPEC-80 (Schedule 80) solutions provide the strength you need with the certification the NEC requires.