UL94 fire testing and other standards (UL / ASTM / ISO)

Impact offer a range of UL94 fire testing services for electronics, as well as further fire testing standards for a range of industries including construction (internal and external).

Need help? Want more information? Get in touch now or phone +44 (0) 1324 489182

UL94 fire testing for flammability of plastic materials for parts in devices and appliances

The UL94 fire testing standard describes five types of fire tests to compare plastics material in terms of their burning behaviour. Each type of test requires a specific gas flow rate, flame height, specimen and flame orientation, and time of exposure to flame. Measurements like afterflame and afterglow times are measured and in some cases calculations regarding burning rate are performed. The results obtained are then compared against a standard set of test criteria and the material is given a rating based on the criteria it satisfies.

The UL94 standard is also similar to ASTM and ISO standards, such as ISO EN 11925-2, ASTM D635, ASTM D3801 and ASTM D5048.

UL94 fire testing, ASTM fire testing, ISO fire testing

find out more

test/activityratingapplication
Horizontal Burning TestHBPlastic materials used to make enclosures for portable, attended, intermittent-duty, household-use appliance (i.e., hair dryers) or for decorative parts.
20mm Vertical Burning TestV-0, V-1 or V-2Plastic materials used to make portable, unattended, intermittent-duty, household-use appliances (i.e., coffee makers).
125mm Vertical Burning Test5VA or 5VBPlastic materials to be used in structural parts, enclosures and insulators in consumer electronic products. This test is the most intense test in UL94.
Thin Material Vertical Burning TestVTM-0,VTM-1 or VTM-2Plastic materials to be used as very thin films, generally not capable of supporting themselves in a horizontal position. These are usually assigned to substrates on flexible printed circuit boards.
Horizontal Burning Foamed Material TestHBF, HF-1 or HF-2Plastic materials for low-density foam materials commonly used in fabricating speaker grills and sound-deadening material.
ISO EN 11925-2
ASTM D635HBPolymeric materials used for parts in devices and appliances.
ASTM D3801V-0, V-1 or V-2Polymeric materials used for parts in devices and appliances. Cannot be used to classify materials used in building construction or finishing.
ASTM D50485VA or 5VBPolymeric materials used for parts in devices and appliances. Cannot be used to classify materials used in building construction or finishing.
Can be used to classify non-metallic materials if found appropriate.
ASTM D4804VTM-0,VTM-1 or VTM-2Plastic materials to be used as very thin films, generally not capable of supporting themselves in a horizontal position. These are usually assigned to substrates on flexible printed circuit boards.
ASTM D4986HBF, HF-1 or HF-2Low density foam materials.
UL94 fire testing

The following figure illustrates the flammability of material in relation to the ratings assigned, 5VA/VB being the least flammable while HB/HBF being the most flammable.

plastic testing

full list of tests