RFOU vs BFOU: What’s the Difference?
Both RFOU and BFOU are offshore and marine power cables rated 0.6/1kV, manufactured to NEK 606. The key difference: RFOU is flame-retardant only (self-extinguishing, IEC 60332), while BFOU is fire-resistant (maintains circuit integrity during fire, IEC 60331). BFOU includes a mica glass tape fire barrier that RFOU does not have. This makes BFOU essential for fire-critical safety circuits and RFOU the economical choice for general offshore power distribution.
TEBAOFLEX manufactures both types. View RFOU product page and BFOU product page for specifications.
Designation Breakdown
| Element | RFOU | BFOU |
|---|---|---|
| R vs B | R = Rubber/EPR insulated | B = Fire resistant (IEC 60331) |
| F | Flexible conductor | Flexible conductor |
| O | Oil-resistant sheath | Oil-resistant sheath |
| U | LSZH outer sheath | LSZH outer sheath |
| Standard | NEK 606 / IEC 60502 | NEK 606 / IEC 60331 |
| Fire Barrier | No mica glass tape | Mica glass tape (yes) |
Performance Comparison
| Property | RFOU | BFOU | Advantage |
|---|---|---|---|
| Fire resistance (IEC 60331) | No | Yes (750-950°C, 90+ min) | BFOU |
| Flame retardancy | IEC 60332-3-22 Cat A | IEC 60332-3-22 Cat A | Tie |
| Smoke density | IEC 61034 (>60%) | IEC 61034 (>60%) | Tie |
| Halogen content | Zero halogen (LSZH) | Zero halogen (LSZH) | Tie |
| Voltage rating | 0.6/1kV | 0.6/1kV | Tie |
| Conductor temp | 90°C | 90°C | Tie |
| Oil resistance | Good (IR2) | Good (IR2) | Tie |
| Mechanical protection | Steel wire braid | Steel wire braid | Tie |
| Cost | Lower (reference) | ~20-30% higher | RFOU |
When to Choose RFOU
- General power distribution: Non-fire-critical circuits don’t require fire resistance
- Process equipment: Production equipment that will be shut down during emergency
- Normal lighting: Non-emergency lighting circuits
- HVAC: Standard ventilation and air conditioning
- Motor power: LV motor supply for non-safety equipment
- Cost optimization: RFOU is 20-30% less expensive — use where fire resistance isn’t required
When to Choose BFOU
- Fire pumps: Must maintain power during fire — only BFOU (IEC 60331) guarantees this
- Emergency lighting: Escape route lighting must remain lit during fire
- ESD systems: Emergency shutdown requires fire-survivable power
- Emergency generator output: Power must reach emergency switchboard during fire
- Alarm/communication: Fire alarms and PA systems need continuous power
- Mandatory by code: SOLAS and classification rules require IEC 60331 cable for critical safety circuits
Cost Comparison
RFOU is the baseline cost. BFOU costs 20-30% more due to:
- Mica glass tape fire barrier material and wrapping process
- More stringent testing (IEC 60331 fire test)
- Additional quality control for fire-critical applications
Best practice: Use BFOU only where fire resistance is mandatory, and RFOU for all other circuits. This optimizes cost while meeting all safety requirements.
Can RFOU and BFOU Be Interchanged?
BFOU can replace RFOU — it has all RFOU properties plus fire resistance. But this adds unnecessary cost for non-critical circuits.
RFOU cannot replace BFOU — RFOU lacks the fire barrier and IEC 60331 rating. Substituting RFOU for BFOU in fire-critical circuits violates classification rules and compromises safety.
Summary: Which Cable Should You Choose?
| If your application is… | Recommended cable |
|---|---|
| General offshore power distribution | RFOU |
| Process equipment, motors, HVAC | RFOU |
| Normal (non-emergency) lighting | RFOU |
| Fire pump, emergency systems | BFOU (mandatory) |
| Escape route emergency lighting | BFOU (mandatory) |
| Emergency generator output | BFOU (mandatory) |
Contact TEBAOFLEX engineering for expert offshore cable selection and competitive pricing on both RFOU and BFOU cables.
