Rigid-flex printed circuit boards (PCBs) combine ideal design elements of both rigid and flexible circuits into a single, versatile electronic package. Their hybrid design allows them to be folded or bent to fit confined or irregularly-shaped spaces while still maintaining rigidity in areas that require more support. Due to the mission-critical nature of the applications they integrate with, rigid-flex PCBs must meet certain standards and qualifications to verify their safety and performance. Among these qualifications is the difficult-to-obtain UL 94 V-0 certification, which is a safety standard pertaining to a PCB’s flammability.
In this blog, we highlight the details of the UL 94 V-0 certification and the advantages of partnering with a UL 94 V-0-certified rigid flex PCB manufacturer capable of providing it.
What is UL 94 V-0 Certification?
Underwriters Laboratory (UL) is a third-party safety science organization that develops comprehensive standards and testing procedures aimed at validating the physical and environmental safety of products. The purpose of the UL 94 V-0 certification is to ensure fire protection and electrical safety of electronic components. A UL 94 V-0 rating indicates that the product can tolerate a certain amount of exposure to a flame without igniting.
Electronics designers and fabricators are often required to obtain UL recognition to prove the viability of their products and meet liability insurance carrier requirements. Acquiring this certification can be challenging due to the rigorous and thorough nature of the testing process. It essentially requires separate testing for each individual component used in a product’s design, which can quickly become overwhelming, expensive, and time-consuming.
Why is UL 94 V-0 Certification Advantageous for Rigid Flex PCB Constructions?
When it comes to product safety, UL has a long-standing track record of integrity. By providing unbiased confirmation of safety, the UL mark communicates to consumers that the product can be trusted and allows them to feel more confident in purchasing it. For PCB manufacturers, UL certification represents alignment with the best safety practices in the industry, giving them a major advantage over competitors.
The growing popularity of rigid flex PCB technology in mission-critical aerospace, medical, and military applications has generated a high demand for UL 94 V-0 recognition among PCB fabricators in order to demonstrate the safety of their products and comply with insurance carrier requirements. To obtain this qualification for their customers, rigid flex PCB fabricators tend to use one of the following three approaches:
- Submitting individual constructions.One option is to submit the constructions for UL recognition one material set at a time. This can become an extremely expensive and time-consuming process, especially if changes in the product’s materials or configuration are required after submission. Even slight material modifications after obtaining the initial certification will disqualify the part from UL recognition.
- Specifying UL 94 V-0-rated materials.Some fabricators attempt to work around the individual sampling and testing requirements by specifying that the board be constructed with UL 94 V-0-certified materials. The error in this approach is that it does not translate to UL certification of the resulting PCB board and fails to meet insurance carrier requirements.
- Mixing and matching individually certified constructions.Less informed board fabricators sometimes make the faulty assumption that individually certified flexible circuit constructions and rigid board constructions can be mixed and matched without testing and verifying the resulting new constructions. However, UL’s letter of recognition clearly states that any changes in construction after the product was originally evaluated will invalidate the UL mark.
Because of Printed Circuits’ comprehensive UL 94 V-0 qualification for rigid flex circuits, customers can now have a single source for fully-compliant circuit boards that meet their insurance carrier requirements. The majority of constructions can be certified immediately, eliminating the expensive and lengthy process of submitting and testing individual board constructions.
UL Certified Rigid Flex PCBs at Printed Circuits
With over 38 years of expertise in rigid flex PCB design and construction, Printed Circuits has developed an expertise in creating fail-proof board solutions for a wide range of demanding applications. Our UL 94 V-0 recognition on most popular rigid flex PCB designs provides buyers and designers with immediate access to UL-certified boards without the usual costs and delays. As demonstrated by our prestigious certifications and accreditations, we are committed to producing high-quality products and meeting stringent industry standards.
For additional information regarding rigid flex PCBs and our specific design and fabrication capabilities, please see the following resources:
- eBooks & Brochures
- Why Rigid Flex PCBs?
- Rigid Flex Design Guidelines
- Rigid Flex FAQ
- Equipment & Capabilities