What you need to know about UL Classifications?

UL classifications are used across many industries, however what does the classification mean for customers.

What does UL stand for?

Underwriters Laboratories (UL) is a leading independent organisation which tests and certifies product safety. Every year the company examines over 19,000 types of products, components, materials and systems.

UL Classification Logo

Why are UL classifications important? 

UL classifications indicate the product is safe and has been tested and evaluated against specific properties and hazards. Once a manufacturer has passed all tests within a given standard, they will be given the UL mark.

A product with the UL mark provides customers with confidence and reassurance in the products safety. Audits are performed on a regular basis by an independent test laboratory to ensure the product continues to follow relevant guidelines and compliance with the UL.

UL94 Standards 

One of the most widely recognised testing standards is UL94; the flammability standard for plastic materials used for parts in devices and appliances.

Manufacturers are increasingly choosing adhesives with a UL94 classification.

Fire retardant adhesives can help extinguish the flames and slow the spread of a fire. Fire retardant adhesives can be used for potting and encapsulating electronics, for cladding and flooring and bonding composite panels, fixtures and fittings in aircrafts and other transport.

UL94 Testing

UL94 is a material burning test and can be either a Horizontal Burn (UL94 HB) test or Vertical Burn (UL94 V) test. In both tests, an open flame is applied to the specimen for a set amount of time. The tests are used to determine the material’s behaviour to extinguish or spread the flame.

The material is classified according to HB, V0, V1 or V2 and the thickness of the specimen is taken into consideration. 5VB and 5VA classifications are related to a bonded panel rather than an adhesive. A material that complies with the UL94 V0 rating is considered more flame retardant than the UL94 V2 rating.

UL94 Testing

UL94 Classifications 

  • HB: slow burning on a horizontal specimen. Burn rate <76mm/min for thickness <3mm or burning stops before 100mm
  • V-2: (vertical) burning stops within 30 seconds and any drips may be flaming
  • V-1: (vertical) burning stops within 30 seconds and drips are allowed but must not be burning
  • V-0: (vertical) burning stops within 10 seconds and drips are allowed but must not be burning
  • 5VB: (vertical plaque specimen) burning stops within 60 seconds, no drips, plaque specimen may develop a hole.
  • 5VA: (vertical plaque specimen) burning stops within 60 seconds, no drips and the plaque specimen may not develop a hole.

Featured UL94 Listed Products

At Antala, we have many products that are tested and compliant to UL94 V-0 or UL94 V-1 and can be used in industrial applications where fire retardancy is essential.


A polyurethane, halogen free, casting and impregnating system for pressure sensitive devices.


An isocyanate free, epoxy-based encapsulation, impregnation and filling system for small transformers, filters, capacitors, coils and electronic circuits.


A resilient casting system exhibiting good resistance to thermal ageing and good thermal shock resistance. Suitable for bonding induction components, transformer, generators and motors, pressure-sensitive components.


A two component structural adhesive for bonding sandwich panels, wall cabinets, partition walls, transformers, drivers control panel and cables.

ARALDITE CW 229-3/HW 229-1

A two component, brown epoxy casting system with high crack and thermal shock resistance. This system is used as an indoor electrical insulation material.


A flexible, multipurpose epoxy casting system with good dielectric properties and resistance to temperature variations. This system can be used for generators and motors.

ARALDITE CW 1305/HY 1300

A two component, epoxy encapsulation system with good thermal shock resistance and thermal endurance. This system can be used for encapsulating heat-evolving components.

Dowsil 7091

A high performance, neutral cure silicone sealant used as a formed-in-Place Gasket (FIPG) material.

More than a distributor. We are your technical partner.

If you have any questions or want to find out more about the possibilities for your industrial application, please complete the contact form and one of our experts will be in touch.

If you have a problem with industrial adhesives, sealants, or electronic protection products and require advice, you can contact our technical support service. Our team can help you to optimize your processes and applications.

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We look forward to optimising your applications through our technologies.


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