UL 3573 Silicone Rubber Ignition Wire — 200°C / 10,000V AC / Three-Layer Construction
UL AWM Style 3573 is a high-voltage silicone rubber ignition lead wire rated 200°C and 10,000V AC under UL Subject 758. The construction uses three layers: extruded silicone rubber inner insulation (30 mils min average / 27 mils min at any point), a fiberglass braid or serve intermediate covering, and an additional extruded silicone rubber outer insulation (10 mils min at any point over the braid). The permitted use covers electronic ignition or similar applications in gas ranges and gas or fuel oil burner systems, where the wire is protected from damage during handling, installation, and servicing of the appliance.
For the two-layer UL 3304 construction (SR 40 mils + fiberglass braid, without outer silicone layer) at the same 10,000V AC / 200°C rating, see UL 3304.

Technical Specifications — UL AWM Style 3573
| Parameter | Specification |
|---|---|
| UL AWM Style | 3573 |
| UL Subject | 758, Section 3 |
| Temperature rating | 200°C maximum |
| Voltage rating | 10,000V AC |
| AWG range | 22 AWG – 12 AWG, solid or stranded |
| Inner insulation | Extruded silicone rubber (SR) — 30 mils min average / 27 mils min at any point |
| Intermediate covering | Fiberglass braid or serve |
| Outer insulation | Extruded silicone rubber (SR) — 10 mils min at any point over braid |
| Conductor | Solid or stranded copper; bare or tinned |
| Flame rating | Horizontal flame |
| UL recognition | UL Recognized Component — file on record |
| Permitted use | Electronic ignition or similar application in gas ranges or gas or fuel oil burner systems — protected from damage during handling, installation, and servicing |
| RoHS / REACH | Documentation available on request |
Construction Detail
UL 3573 uses a three-layer construction. The inner silicone rubber insulation (30 mils min average) provides the primary dielectric barrier for the 10,000V AC rating. The intermediate fiberglass braid or serve provides mechanical reinforcement. The outer silicone rubber layer (10 mils min at any point) covers the braid surface. This differentiates UL 3573 from UL 3304, which uses a two-layer construction (silicone rubber insulation + fiberglass braid as outermost layer, without an outer silicone jacket).
Common Applications
Gas range and cooktop ignition leads
Internal ignition lead wire connecting the electronic ignition module to the spark electrode in gas cooking ranges and cooktops. The wire must be routed in a protected internal path within the appliance enclosure, protected from damage during handling, installation, and servicing as required by the UL permitted use.
Fuel oil burner ignition leads
High-voltage lead from the ignition transformer to the spark electrodes in fuel oil burner assemblies for residential and commercial heating boilers. Wire routing must be protected from mechanical damage within the burner enclosure.
Commercial gas burner systems
Internal ignition lead routing in commercial gas burner assemblies used in restaurants, industrial food service operations, and process heating equipment, where the wire is routed in a protected internal path within the equipment housing.
Other applications
- Gas barbecue and outdoor heater electronic ignition leads — protected internal routing
- Infrared gas heater ignition systems
- Commercial catering equipment ignition wiring
Request a Quote
Specify AWG, conductor type (bare / tinned), colour, spool length, and quantity. Custom AWG sizing and stranding configurations available — confirm at enquiry stage. UL compliance documentation available on request. Response within 12 hours.






