EPDM Insulation, also known as Ethylene Propylene Diene Monomer, is synthetic rubber insulation. Created using a chemically cross-linked elastomer, EPDM is one of the most flexible, durable and resistant compounds on the market. 

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EPDM performs very well in highly demanding application environments, as it is extremely resistant and very reliable. Listed below are just of the ratings for this type of material. These are the standard ratings, but some that aren't mentioned are oils, like gasoline and kerosene, which EPDM is very weak against.

EPR, which is the earlier relative, Ethylene-propylene rubber, doesn't contain any Diene. Some of the different Dienes that are used in the manufacturing of EPDM rubber are ENB (Ethylidene norbornene), DCPD (Dicyclopentadiene), and VNB (Vinyl norbornene).


Temperature Rating Flexibility Durability Moisture Resistance UV Resistance Chemical Resistance Fire Resistance
-55°C to +125°C  Excellent Great Good Good Poor Poor


Mechanical Properties of EPDM

Property Value
  • Hardness, Shore A
  • 30-90
  • Tensile failure stress, ultimate              
  • - 25 MPa (500-2500 PSI)
  • Elongation after fracture in %

  • ≥ 300%
  • Density
  • Can be compounded from 0.90 to >2.00 g/cm3    


Thermal Properties of EPDM

Property Value
  • Coefficient of thermal expansion, linear                 
  • 160 µm/(m·K)                                     
  • Maximum service temperature

  • 150°C
  • Minimum service temperature

  • −50°C
  • Glass transition temperature
  • −54°C

Standard EPDM Applications

  • Lead Wire in constructions consisting of UL3340, UL3374, & UL3399.
  • Hook-Up Wire in construction consisting of CSA 1254, UL3824 & UL3374
  • Used in direct burials
  • Power cables
  • Appliance wiring
  • Internal wiring
  • Welding cable

Bundled EPDM Wires

EPDM is consistently used because of the numerous benefits it's able to bring to applications, but this material also has some specific weaknesses. The EPDM material is most effectively used for applications in a specific setting because even if the application is extremely demanding, if the environment is right, EPDM wire and cable can perform consistently for extended periods of time.


EPDM Benefits

  • Flexible
  • Reliable
  • Good solution industrial applications
  • A strong solution for appliance wiring for motors and transformers
  • Resistance to Moisture
  • Resistance to UV
  • Perfect for medium volt applications and testing

EPDM Weaknesses

  • Poor Resistance to Chemicals
  • Poor Resistance against applications that have gasoline, oil, and kerosene.
The CL1245, UL3340 is approved for applications in Class 130(B), 155(F) and 180(H) environments. This EPDM insulated is also known for its ability to operate at silicone temperature ratings but at more cost-effective pricing. CL1254 and UL3340 are approved for different designations, while CL1254 is rated for high-temperature flexing, the UL3340 designation is not.
EPDM CL1254, UL3340 Hook-Up Wire
EPDM is a material that is flexible, strong and typically used in demanding application environments. Being heavily used for durable lead wires, EPDM is available in a number of hook-up wiring constructions. From welding cables to construction cables and even automotive cables, EPDM is able to perform consistently in a wide variety of different environments. If you are unsure which EPDM construction is right for your application, don't hesitate to reach out to our knowledgeable sales team.

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