Understanding OFNP, OFNR, LSZH, and PVC Ratings in Fiber Optic Patch Cables

When selecting fiber optic patch cables for data centers, commercial buildings, or telecom facilities, you may often notice markings such as OFNP, OFNR, LSZH, and PVC on the cable jacket. These terms indicate important information about fire resistance, smoke emission, and installation environments. Understanding their differences ensures both safety compliance and optimal performance in your fiber network infrastructure.

1. What Do OFNP and OFNR Mean?

Both OFNP and OFNR are fire-rating designations defined by the National Fire Protection Association (NFPA) and are widely used in North America to classify fiber optic cables based on their flame-retardant properties.

OFNP – Optical Fiber Nonconductive Plenum

• Definition: The highest fire-resistance rating for indoor fiber optic cables.

• Installation environment: Suitable for plenum spaces, such as air-handling ducts, raised floors, or ceilings used for ventilation.

• Performance:

  • Excellent flame-retardant properties.

  • Very low smoke and toxic gas emission.

  • Often required in high-density buildings or data centers for enhanced fire safety.

• Keyword focus: OFNP plenum cable, fire-resistant fiber optic cable, data center cabling standard.

OFNR – Optical Fiber Nonconductive Riser

• Definition: A slightly lower rating than OFNP, designed for vertical riser shafts or between floors.

• Installation environment: Used in riser applications, such as connecting equipment across building floors.

• Performance:

  • Good flame resistance but not suitable for plenum air spaces.

  • Cost-effective option for most in-building fiber installations.

• Keyword focus: OFNR riser cable, vertical fiber optic cable, building communication wiring.

2. LSZH and PVC: Jacket Materials and Safety Standards

Apart from OFNP/OFNR ratings, the outer jacket material also affects the safety and environmental performance of fiber cables. The two most common types are LSZH (Low Smoke Zero Halogen) and PVC (Polyvinyl Chloride).

LSZH – Low Smoke Zero Halogen

• Definition: Jacket material that emits minimal smoke and no toxic halogen gases when exposed to fire.

• Advantages:

  • Safer for personnel and sensitive equipment.

  • Environmentally friendly and compliant with EU RoHS standards.

  • Ideal for confined public areas, transportation systems, or data centers.

• Keyword focus: LSZH fiber patch cable, low smoke fiber cable, halogen-free optical cable.

PVC – Polyvinyl Chloride

• Definition: A durable, cost-efficient jacket material commonly used in general-purpose applications.

• Advantages:

  • Flexible and easy to install.

  • Provides good mechanical strength and insulation.

  • Best suited for non-critical environments where fire safety is not a major concern.

• Keyword focus: PVC fiber optic cable, durable fiber jacket, cost-effective patch cord.

3. OFNP vs. OFNR vs. LSZH vs. PVC — Comparison Table

4. Choosing the Right Fiber Patch Cable for Your Environment

Selecting the appropriate fiber optic cable depends on your installation site, safety requirements, and regulatory standards:

• Choose OFNP cables for data centers, hospitals, and office buildings where air-handling spaces are present.

• Use OFNR cables for riser installations connecting equipment between floors.

• Opt for LSZH cables in European projects or transportation systems requiring low smoke and zero halogen.

• Select PVC cables for general-purpose networks that prioritize flexibility and cost-effectiveness.

Conclusion

Understanding these designations—OFNP, OFNR, LSZH, and PVC—is crucial for engineers, system integrators, and network managers who prioritize both performance and safety in fiber optic installations.
At RUIARA, we provide a wide range of fiber optic patch cords meeting international fire safety and environmental standards, available in single-mode (OS2) and multimode (OM3/OM4/OM5) configurations with LSZH, PVC, OFNR, and OFNP options.

For technical specifications, OEM customization, or distributor inquiries, contact us or visit www.ruiara.com to learn more.