In a fire, the electrical system has a second job beyond delivering power: keeping emergency lighting, alarms, communications, lifts and fire pumps running long enough for people to get out. That is what circuit integrity means, and it depends almost entirely on the conductor's insulation surviving the fire.
YT MICA supplies mica tape and insulation systems for fire-resistant cables, with the fire and circuit integrity testing to verify performance against the standards your project references.
Mica tape is not merely passive — it forms an inorganic mineral layer around the conductor and keeps it functioning.
When a cable is exposed to fire, its organic insulation — the polymer layers that do the insulating job in normal service — will carbonise, melt or burn away. A mica tape wrapped around the conductor behaves differently. Its mica layer is a mineral, so it does not burn, and it continues to hold dielectric strength after the surrounding polymer has gone.
That surviving mica layer is what prevents phase-to-phase shorts and earth faults, and it is the reason a fire-resistant cable can keep a circuit live while the fire is still burning.
| Mica Category | Fire Resistance Temp. (°C) | Recommended For |
|---|---|---|
| Phlogopite mica tape | 750 – 830 | Standard fire-resistant cables |
| Synthetic mica tape | 950 – 1000 | Cables requiring the highest rating |
| Calcined mica tape | 750 – 950 | Halogen-free fire-resistant cables |
| Coated mica tape | 750 – 950 | Special fire-resistant cable designs |
Mica tape also protects in normal operation. Its high dielectric strength and stable insulation resistance prevent short circuits and leakage, which matters most at high voltage or in extreme thermal environments — including EV high-voltage harnesses and rail transit vehicle cables.
Our test centre covers material property and fire resistance tests complying with IEC 60331, IEC 60371-2, IEC 60371-3-8, EN 50200 and BS 6387. Custom test conditions are available upon request.
Laboratory capabilitiesSend us the fire-resistance class, voltage and cable construction and we will recommend a mica system.
