REFERENCE · JULY 2026
- FR — IS 694:2010 baseline: oxygen index ≥ 29% and IEC 60332-1. Does not regulate HCl or smoke.
A consultant who specifies "HFFR cable for the fire pump" has not specified a fire-pump cable — the fire pump needs a Fire Survival cable.
All five are type-test requirements in IS 694:2010 and IS 17048:2018. BIS-licensed manufacturers must hold a current type-test report against the relevant clauses for their CM/L licence to remain valid.
Alphabetical, not a recommendation. Verify IS standard, BIS licence and type-test certificate in the latest OEM catalogue before specifying.
Cable Fire Performance — FR vs FR-LSH vs HFFR vs HRFR
Indian building wire is sold in four distinct fire-performance grades: FR and FR-LSH (both certified to IS 694:2010), HRFR (IS 694:2010 with 85 °C heat-resistant PVC), and HFFR (a separate Indian standard, IS 17048:2018, also marketed as LSZH / LS0H / ZHFR). None of these four are Fire Survival cables — that is a different product class, governed by IEC 60331 / BS 6387 / IS 17505, and specifying any of the four on a fire-survival circuit is a professional-liability error. This page sets out the quantitative comparison (HCl, smoke density, oxygen index, conductor temperature), the test-method references, and the Engineering Note that distinguishes Reaction to Fire from Fire Survival.
Engineering Note — "Reaction to Fire" is NOT "Fire Survival"
> This is the most-conflated topic in Indian cable specification. Get it wrong on a tender and the consultant carries the liability.
Reaction to Fire describes how a cable behaves during a fire — smoke output, HCl evolution, flame propagation along a bunched run. It does not mean the cable continues to carry current.- Test methods (Reaction to Fire): IS 10810, IEC 60332-1 (single-cable flame), IEC 60332-3 (bunched-cable flame), IEC 60754-1 / 60754-2 (halogen acid gas), IEC 61034-1 / 61034-2 (smoke density).
- Products in this category: FR (IS 694:2010), FR-LSH (IS 694:2010 with HCl < 15%), HFFR (IS 17048:2018 with HCl < 0.5%), HRFR (IS 694:2010 with 85 °C heat-resistant PVC).
- Test methods (Fire Survival): BS 6387 (categories C, W, Z), IEC 60331-21 / 60331-25, IS 17505.
- Products: Mineral-Insulated (MI) cables, mica-tape ceramifiable cables, FR-FS constructions. None are IS 694:2010 / IS 17048:2018 building wires.
The four IS 694:2010 / IS 17048:2018 grades — quantitative comparison
| Property | Plain PVC | FR | HRFR | FR-LSH | HFFR |
|---|---|---|---|---|---|
| Standard | IS 694:2010 (no flame test required) | IS 694:2010 | IS 694:2010 (HR PVC) | IS 694:2010 | IS 17048:2018 |
| Continuous conductor temp | 70 °C | 70 °C | 85 °C | 70 °C | 90 °C (typical) |
| Flame propagation | none specified | IEC 60332-1 | IEC 60332-1 | IEC 60332-1 + IEC 60332-3 | IEC 60332-1 + IEC 60332-3 |
| HCl emission % | n/a (no limit) | not regulated | not regulated | < 15% | < 0.5% |
| Smoke density (light transmittance, IEC 61034) | very low (opaque) | reduced | reduced | improved | > 60% at 3 m |
| Oxygen index (IS 10810 / ISO 4589) | ~21% | ≥ 29% | ≥ 29% | ≥ 29% | ≥ 30% |
| Halogen content | high | high | high | reduced | halogen-free |
| Use case (NBC 2016 indicative) | not used for Indian residential wiring | residential up to G+3 | high-ambient runs, AC circuits, attic | residential G+4+, commercial | hospitals, airports, metro, data centres, public assembly |
- FR-LSH — IS 694:2010 with HCl < 15% per IS 10810 / IEC 60754 and improved smoke density.
- HRFR — FR with heat-resistant 85 °C PVC for AC compressor circuits and high-ambient runs. Not lower-smoke than FR.
- HFFR — separate standard IS 17048:2018, halogen-free: HCl < 0.5%, light transmittance > 60% at 3 m, oxygen index ≥ 30%, typically also IEC 60332-3 bunched-cable compliant.
- HR-FR-LSH — 85 °C HR PVC with HCl < 15%. Polycab Green Wires only (April 2026).
HCl emission — the 30:1 ratio between HFFR and FR-LSH
The acid-gas evolution of burning PVC is the single number that drives the FR-LSH / HFFR specification choice. IS 10810 and IEC 60754-1 measure the mass percentage of HCl released when 1 g of compound is burned at 800 °C.
`` Plain PVC ████████████████████████████████ ~28–30% FR ████████████████████████████████ ~28–30% (no upper limit) FR-LSH ████████████████ < 15% (IS 694:2010 limit) HFFR ▌ < 0.5% (IS 17048:2018 limit) `
The ceiling-to-ceiling ratio between HFFR and FR-LSH is 30 : 1. HCl is acutely toxic at low concentrations and, on contact with water vapour, forms hydrochloric acid that destroys electronics, switchgear and structural steel long after extinguishment. Hospitals, airports, metro stations and data centres specify HFFR for both reasons.
Smoke density — visibility for evacuation
IEC 61034-2 measures smoke density in a 3 m × 3 m × 3 m cube as the percentage of light that transmits across the diagonal while a 1-metre cable sample burns. Higher percentage = clearer air = visible escape route.
`
HFFR (IS 17048:2018) > 60% light transmittance at 3 m ████████████
FR-LSH (IS 694:2010) ~40–60% (improved over FR) ████████
FR (IS 694:2010) ~20–40% (reduced vs plain PVC) ████
Plain PVC < 20% (effectively opaque) ▍
`
In corridor evacuation, the difference between FR and HFFR is the difference between visible exit signage and an opaque smoke layer at head height. NBC 2016 Part 4 references this when mandating cable type for escape routes, atria and assembly occupancies.
When to specify which grade
The decision is driven by NBC 2016 Part 4 occupancy classification and building height. See
/learn/nbc-2016-fire-safety` for the full compliance matrix; the summary below is indicative.
| Building / circuit type | Indicative grade | Rationale |
|---|---|---|
| Residential up to G+3 (Group A-1, A-2) | FR | NBC 2016 minimum; IS 694:2010 baseline |
| Residential G+4 and above | FR-LSH | Smoke + halogen reduction in stair pressurisation routes |
| Commercial (Group E), shopping (Group F) | FR-LSH minimum | Public assembly, evacuation visibility |
| Hospital (Group C-1) | HFFR (IS 17048:2018) | Halogen-free mandated for ICU, OT, patient corridors |
| Airport, metro station, public assembly | HFFR | Crowded escape, electronic equipment protection |
| Data centre | HFFR | Electronics survival post-event |
| AC compressor / high-ambient circuit | HRFR | 85 °C conductor temperature |
| Specialised residential premium | HR-FR-LSH | Polycab Green Wires only |
| Fire-pump feeder, lift-recall, smoke-extraction control | NOT THIS PAGE — Fire Survival cable to BS 6387 / IEC 60331 / IS 17505 | Reaction-to-Fire grades do not satisfy circuit-integrity requirement |
How fire-performance is tested
IS 694:2010 and IS 17048:2018 reference IEC test methods directly (with parallel IS 10810 methods for Indian-witnessed BIS testing). The four families of tests are:
| Test | What it measures | Standard |
|---|---|---|
| Single-cable flame propagation | A 600 mm cable sample held vertically is exposed to a 1 kW propane flame for 60–480 s; char must not exceed 50 mm above the burner. | IEC 60332-1-2 |
| Bunched-cable flame propagation | A 3.5 m vertical ladder of bunched cables is ignited; the char height after a defined burn time classifies the bundle as Cat A / B / C / D. FR-LSH and HFFR cables must pass at least Cat B. | IEC 60332-3-22 / -23 / -24 |
| Halogen acid gas (HCl) | 1 g of compound is burned in a tube furnace at 800 °C; evolved HCl is absorbed and titrated. Reported as mass %. | IEC 60754-1 (mass), IEC 60754-2 (pH + conductivity) |
| Smoke density | A 1 m horizontal cable sample is burned in a 27 m³ cube under defined conditions; light transmittance across the diagonal is measured. | IEC 61034-1 / IEC 61034-2 |
| Oxygen index | The minimum %O₂ in an O₂/N₂ mixture that sustains combustion of a vertical specimen. | IS 10810 Pt 58 / ISO 4589-2 |
Brand product lines and which grade they cover
Listed alphabetically by brand. Verify the BIS CM/L licence number against the brand's current ISI marking on bis.gov.in before procurement.
| Brand | Product line | Grade(s) |
|---|---|---|
| Finolex | Finolex FR / Finolex FR-LSH | FR, FR-LSH |
| Havells | Life Line+ S3 | HRFR (IS 694:2010, 85 °C HR PVC) |
| Havells | Life Guard | FR-LSH (IS 694:2010, HCl < 15%) |
| Havells | Life Shield | HFFR (IS 17048:2018, HCl < 0.5%) |
| KEI | HOMECAB | FR (IS 694:2010) |
| KEI | CONFLAME | FR-LSH (IS 694:2010, HCl < 15%) |
| KEI | BANFIRE | HFFR (IS 17048:2018, HCl < 0.5%) |
| National Cables | National FR / National FR-LSH | FR, FR-LSH |
| Polycab | Polycab FR / FR-LSH | FR, FR-LSH |
| Polycab | Green Wires | HR-FR-LSH (IS 694:2010, HR PVC + HCl < 15%) |
| RR Kabel | RR FR / FR-LSH / HFFR | FR, FR-LSH, HFFR |
Frequently asked questions
What is the difference between FR and FR-LSH?
Both are IS 694:2010. FR requires IEC 60332-1 flame retardance and oxygen index ≥ 29%, but does not regulate HCl or smoke density. FR-LSH adds two requirements: HCl < 15% per IS 10810 / IEC 60754, and improved smoke density per IEC 61034. FR-LSH is typically 8–15% above FR at list.
What is the difference between FR-LSH and HFFR?
They are governed by different Indian standards. FR-LSH is IS 694:2010 with HCl 60% at 3 m, and oxygen index ≥ 30%. The HCl ceiling ratio between the two is 30 : 1.
What does HFFR mean? (a.k.a. LSZH / ZHFR / LS0H)?
HFFR stands for *Halogen-Free Flame-Retardant*. The same product is marketed internationally as LSZH (Low Smoke Zero Halogen), LS0H (Low Smoke Zero Halogen, with a numeric zero), or ZHFR (Zero Halogen Flame Retardant). In India the standard is IS 17048:2018, with HCl < 0.5% and smoke density per IEC 61034.
Is FR-LSH a fire-survival cable?
No. FR-LSH is a *Reaction to Fire* grade — it controls smoke and acid-gas evolution while burning but does not maintain circuit integrity. *Fire Survival* cables are a separate class certified to BS 6387 (categories C/W/Z), IEC 60331-21 or IS 17505 — typically mineral-insulated or mica-tape constructions used for fire-pump power, lift-recall, smoke extraction and emergency lighting. Specifying FR-LSH on a fire-survival circuit is a non-compliance.
What is the HCl emission limit for FR-LSH?
Less than 15% by mass when tested per IS 10810 / IEC 60754-1, as required by IS 694:2010 for the FR-LSH grade. The plain FR grade has no HCl upper limit; HFFR (IS 17048:2018) tightens the limit to less than 0.5%.
What is the smoke density limit for HFFR?
IS 17048:2018 (referencing IEC 61034-2) requires light transmittance greater than 60% at 3 m in the standard 27 m³ smoke cube during the burn of a 1 m cable sample. This is the figure used for evacuation-visibility design in NBC 2016 escape routes.
Which IS standard covers HFFR cable?
IS 17048:2018 — the Indian Standard for halogen-free flame-retardant insulated cables. It is a separate standard from IS 694:2010, has a separate BIS licence (different CM/L number), and prescribes its own type tests for HCl, smoke density, oxygen index and bunched-cable flame propagation (IEC 60332-3).
Is HRFR the same as FR-LSH?
No. HRFR is IS 694:2010 FR-grade insulation made with heat-resistant 85 °C PVC — it raises the continuous conductor temperature from 70 °C to 85 °C for use on AC compressor circuits, attic runs and high-ambient locations. It does not improve HCl or smoke density. FR-LSH is IS 694:2010 FR-grade with HCl < 15% — it improves smoke and halogen at the standard 70 °C conductor temperature. They solve different problems and are sometimes combined as HR-FR-LSH (Polycab Green Wires).
What test method verifies HFFR compliance?
IS 17048:2018 references four type tests: IEC 60332-1 (single-cable flame), IEC 60332-3 (bunched-cable flame, typically Category B or better), IEC 60754-1 for HCl mass percentage and IEC 60754-2 for smoke pH and conductivity, and IEC 61034-2 for smoke density (light transmittance > 60% at 3 m). Oxygen index per IS 10810 Pt 58 / ISO 4589-2 must be ≥ 30%. BIS licensees must hold a current type-test report against all four clauses.
Why does NBC 2016 mandate HFFR for hospitals?
Two reasons. Patient evacuation in ICU, OT and ward corridors depends on visibility — HFFR's > 60% light transmittance at 3 m keeps escape routes navigable. Electronic equipment survival — monitors, ventilators, switchgear and BMS are corroded by HCl mist within minutes of a PVC fire even after extinguishment; HFFR's HCl < 0.5% ceiling prevents this. NBC 2016 Part 4 references both for Group C-1 occupancies.
What is the oxygen index of HFFR vs FR?
FR (IS 694:2010): oxygen index ≥ 29%. HFFR (IS 17048:2018): oxygen index ≥ 30%. Both are well above the ~21% atmospheric oxygen level, so neither sustains self-combustion once the external ignition source is removed. Plain PVC is ~21–23%. Measured per IS 10810 Pt 58 / ISO 4589-2.
Does HFFR cable cost more than FR?
Yes. Indicative list-price premium over plain FR, April 2026: FR-LSH +8–15%, HRFR +5–10%, HFFR +25–40%. The HFFR premium reflects polyolefin compound cost and the separate IS 17048:2018 BIS licence. For current side-by-side comparison across brands, see the FR / FR-LSH / HFFR category pages.
METHODOLOGY
Updated weekly by the cablepriceindia.com price-research desk. Last verified: 12 July 2026. Sources cited inline. We are an independent price-discovery service. Verify any BIS Conformity Marking Licence (CM/L) at bis.gov.in.