FR Single Core Wire — Flame Retardant

Both are covered under IS 694:2010 but use different insulation compounds. FR (Flame Retardant) wire uses standard PVC with flame-retardant additives — it slows flame propagation but still releases dense black smoke and halogen acid gas during combustion.

FR-LSH (Flame Retardant Low Smoke Halogen) uses modified PVC formulated to reduce smoke density and halogen emission, improving visibility and reducing corrosive fumes in a fire. FR-LSH is generally specified for buildings over 15 metres or high-occupancy enclosed spaces per National Building Code guidance.

Full comparison: FR vs FR-LSH vs LSZH →

See our FR-LSH Single Core Wire specifications for low-smoke applications.

The ISI mark confirms that the wire is covered by a valid BIS licence and is manufactured to conform to IS 694:2010. BIS issues the licence after auditing the manufacturer's production facility, quality management systems, and product test samples.

National Cables holds BIS licence CM/L-8800140116 for IS 694:2010, verifiable at bis.gov.in. Always check that both the ISI mark and the printed licence number appear on the cable sheath — an unqualified "ISI" mark without a licence reference should not be accepted as proof of compliance.

Standard FR single core wire to IS 694:2010 using Type A PVC insulation has a maximum continuous conductor operating temperature of 70°C. Heat-resistant variants such as HR grade may be rated up to 85°C under the same standard, but require separate specification.

The actual current-carrying capacity at a given ambient temperature is lower than the conductor limit suggests, because derating factors apply above 30°C ambient. Refer to the ambient de-rating table above for installation temperature corrections.

Yes. FR wire uses a PVC base compound with flame-retardant additives that resist flame spread, but the PVC material itself generates dense black smoke and toxic halogen acid gas (hydrogen chloride) during combustion. More than 80% of fire-related casualties are caused by smoke inhalation and visibility loss rather than direct flame contact.

If low smoke emission is required — particularly in enclosed public spaces, high-rise buildings, or hospitals — specify FR-LSH wire (IS 694:2010 FR-LSH category) or HFFR wire (IS 17048:2018) instead.

No. FR wire to IS 694:2010 uses PVC (polyvinyl chloride) insulation, which inherently contains chlorine — a halogen. When combusted, PVC releases hydrogen chloride gas (HCl), which is toxic and highly corrosive to electronics and building materials.

For halogen-free construction (zero chlorine, bromine, or fluorine), specify HFFR / LSZH wire manufactured to IS 17048:2018, which uses halogen-free polyolefin insulation. National Cables holds BIS licence CM/L-8800227819 for IS 17048:2018.