Functional safety certification has benefits far beyond compliance.
By Bill Lamie, President/ CEO at PX5 RTOS.
Functional safety is top- of-mind for developers of safety-critical devices in the automotive, industrial, and medical industries. This also impacts security since a device with functional safety vulnerabilities is also easier to compromise.
The use of a real-time operating system (RTOS) in a safety-critical system requires that the embedded RTOS also undergoes rigorous verification. This
is especially true when regulatory certification is mandatory and specific documentation and testing processes for the targeted safety standards are required.
What is FSC for RTOS?
RTOS functional safety certification (FSC) is an objective measure of proper operation and, by extension, quality. For example, an RTOS certified for functional safety requires 100% C statement testing coverage and 100% branch/decision testing coverage. It also requires a verified software lifecycle and a safety manual to ensure developers use the embedded RTOS correctly. This represents a level of rigor above and beyond common RTOS solutions. This extra rigor equates to industry best practices.
The need for FSC for RTOS
A certified RTOS is analogous to the foundation of a building. If the foundation isn’t strong, the entire building might fail. The same is true for embedded software applications. If the RTOS is faulty, the whole application might fail. Yet today, with more than 100 open-source and commercial RTOSes in the embedded development market, most of them don’t have functional safety certification.
Here’s why this is important. In addition to mandatory regulatory certification, many integrators and end users require it to provide the highest level of confidence in the following:
1) The safety-related part of a product/system is designed to be safe and can be operated safely to the extent required by a safety target.
2) The safety functions are based on an assessment and understanding of the risks posed by the product/system/ application.
Easier path to FSC for RTOS
If RTOS FSC seems daunting and time consuming, a new off- the-shelf FSC for the PX5 RTOS allows embedded developers to leverage this certification in conjunction with their embedded software certification to build a safety-certified device for the automotive, industrial, and medical industries as well as for non-safety-critical devices.
PX5 RTOS certifications were performed by SGS- TÜV Saar, the leading accredited, independent company for testing, auditing, verifying, and certifying embedded software for safety-related systems. PX5 RTOS achieved functional safety certification to the highest levels of the IEC 61508, IEC 62304, ISO 26262, and EN 50128 functional safety standards, specifically IEC 61508 SIL 4, IEC 62304 Class C, ISO 26262 ASIL D, and EN 50128 SW-SIL 4.
Benefits for embedded software devices
A pre-certified RTOS provides great value for devices that require FSC. The documentation can be used in the device’s certification, saving developers from trying to certify the RTOS code in addition to the application code. Instead, they simply supply the embedded RTOS certification artifacts with the application certification, thereby saving considerable time and money.
Even if your embedded application doesn’t have an explicit FSC requirement today, it might in the future. There is an ever-increasing stream of new legislation concerning product safety and security, e.g., General Product Safety Regulation (GPSR), EU Machinery Regulation, European Medical Device Regulation (EU MDR), European Cyber Resilience Act (CRA), and more. A certification helps futureproof your device against that eventuality.
Following industry best practices is an essential first line of defense in product liability. A certified RTOS has extensive functional safety testing, which helps improve the overall device quality and reduces the risk of recall when the device is in production.
Since embedded RTOS FSC benefits all devices and represents industry best practices, it should be a “must have” in the embedded market. Device makers that leverage an RTOS with FSC improve time-to-market and product quality and reduce product liability.