In an earlier blog concerning CAPLINQ’s UL Certification policy, it was outlined how CAPLINQ supports its customers with the UL certification of polyimide and other tapes. This time, the differences between UL94 V-0 and UL94 VTM-0 will be described.
Certification Classification
For tapes and other thin materials, the certification classification typically used is UL94 VTM-0. The UL94 V-0 code is used for a self supporting material. The problem that arises with a very thin material is that it may not burn but it will shrink or distort as the flame is directed to the sample and if it cannot withstand a ten second application before in shrinks to the holding clamp, so it will not be classified as a 94V material. Cases like this are what UL 94VTM is used for. You take a sheet 200mm X 50m and form a cone with it to perform the flame test as shown in the figure. Many thin materials that will not burn but will shrink to the clamp and need VTM testing.
Vertical Testing of Thin Materials (VTM-0, VTM-1, VTM-2)
This test is used for materials that are thin, or are too flexible or may distort, shrink or flex during ordinary vertical testing. Procedure: An 8×2 in specimen is rolled longitudinally around a 1/2 in diameter mandrel and taped on one end. When the mandrel is removed the specimen forms a cone. The cone is supported in a vertical position and a flame is applied to the bottom of the specimen. The flame is applied for three seconds and then removed until flaming stops at which time the flame is reapplied for another three seconds and then removed. Two sets of five specimens are tested. The two sets are conditioned under different conditions.
Vertical Flame Test for Thin Materials
| Vertical Rating for Thin Materials |
Requirements |
|---|---|
| VTM-0 |
|
| VTM-1 |
|
| VTM-2 |
|
For more information of UL classification or polyimide tapes, visit us or contact us for more details.
Outstanding post but I was wondering if you could write a litte more on this topic?
I’d be very grateful if you could elaborate a little bit more.
Appreciate it!
Since most solder resists only have a V-0 rating because they have been tested ona FR4.0 carrier I was wondering if a solder rests for flex that passed VTM-0 on polyimide would be considered more flame resistant than a regular Soldermask on FR4.0?
May I know the differences between V-0 and HF-1 rating when we tested to UL 94 for thermal insulation made from NBR (Nitrile Rubber)?
Because I checked on UL listed directory with the same material (NBR) but you have 2 results V-0 and HF-1 also.
Do you have any comparison which is better?
When we have to use V-0 rated and when HF-1 rated?
UL94 is the standard for safety of flammability of plastic materials for parts in electrical equipment and accessories. There are different versions of this standard for different type of materials whereof UL94 V is the most common, however this test is not suitable for all types of plastic materials. For some specific cases a separate method and set of classifications has been created. For example, the UL94 HBF standard is specifically for foams and the UL94 VTM standard is for thin materials. HF-1 is one of the possible classifications from the UL94 HBF standard.
What is the purpose of 7 days conditioning process for UL94V0?
I am looking for a fireproof bag and found one that stated… “It is made of double layered non-itchy silicone coated fiberglass which stands up the temperature up to 2000℉.It has been passed by SGS TEST(UL94 VTM-0 Certified). ” Is this good or bad? What type of certification should I look for to keep important papers safe from fire and water?
The fireproof bag you described seems to have some promising features, but it’s essential to understand the certifications and materials to ensure it will adequately protect your important papers from fire and water damage.
Here are some key points to consider:
Material: The bag is made of double-layered non-itchy silicone coated fiberglass, which is a common fire-resistant material. This is a good sign as it suggests the bag should withstand high temperatures.
Temperature Rating: The bag claims to withstand temperatures up to 2000℉. This is an excellent temperature rating and should provide substantial protection for your documents in most house fires, as typical house fires rarely exceed this temperature.
SGS Test and UL94 VTM-0 Certified: The fact that it has passed SGS testing and is UL94 VTM-0 Certified is a positive sign. SGS is a reputable global testing and certification organization, and UL94 VTM-0 is a fire testing standard for flammability of plastic materials. A VTM-0 rating indicates the material’s high resistance to burning, which is beneficial for a fireproof bag.
Water Resistance: While the bag is primarily advertised as fireproof, you should also consider its water resistance. Many fireproof bags are also designed to be water-resistant, which can be important in case your documents are exposed to water during firefighting efforts.
Size and Capacity: Ensure the bag is large enough to hold all the important documents you want to protect. Some bags are larger than others, so choose one that suits your needs.
Additional Features: Some fireproof bags come with extra features like a carrying handle, shoulder strap, or inner pockets for better organization.
When choosing a fireproof bag to protect important documents from fire and water damage, look for certifications like UL94 VTM-0 or UL72 for fire resistance. Also, consider independent testing from reputable organizations like SGS. Make sure the bag meets your size and capacity requirements, and if water resistance is essential, check for that feature as well.
Keep in mind that no fireproof bag can provide absolute protection against all conditions, but a high-quality bag with the right certifications should significantly increase the chances of preserving your important documents in case of a fire or water-related incident.
The 7-day conditioning process for UL94V-0 testing is an important step in assessing the fire resistance of plastic materials and products. UL94 is a standard established by Underwriters Laboratories (UL), a globally recognized safety testing and certification organization. The UL94V-0 rating is a specific classification within this standard.
The purpose of the 7-day conditioning process is to simulate the effects of aging on a plastic material before subjecting it to flammability testing. This process helps ensure that the material’s fire resistance remains consistent over time and is not significantly affected by environmental factors or aging. Here’s why it’s necessary:
Realistic Testing: Materials, especially plastics, can change their properties over time due to exposure to environmental factors like humidity, temperature fluctuations, and UV radiation. These changes could affect a material’s flammability characteristics. The 7-day conditioning process provides a controlled environment to age the material in a way that’s similar to real-world conditions.
Consistency: By subjecting the material to a consistent aging process, the testing aims to ensure that the material’s fire resistance remains consistent from one batch to another and over time. This helps manufacturers and consumers have confidence in the material’s performance.
Safety: The UL94V-0 rating is the highest level of fire resistance within the UL94 standard. Materials that achieve this rating are deemed self-extinguishing and are less likely to contribute to the spread of flames in case of a fire. To maintain safety standards, it’s crucial that the material’s fire resistance remains stable.
Reliability: UL94V-0-rated materials are often used in applications where fire safety is critical, such as electronics and electrical equipment. The 7-day conditioning process helps ensure the reliability of these materials in such applications.