This white paper describes the distinction between failure rate prediction and estimation methods in general and then gives an overview of the procedures used to obtain dangerous failure rates for certain mechanical equipment using exida FMEDA predictions and OREDA estimations. exida frequently compares field failure rate data from various sources to FMEDA results in order to validate the FMEDA component library. However, because OREDA and FMEDA methods are quite different, it is not possible to compare their results directly. A methodology is presented which creates predictions and estimations that are more comparable. The methodology is then applied to specific equipment combinations and the results are compared. When differences in the results exist between the two methods, plausible explanations for the differences are provided.

The comparisons show that the OREDA failure rates are well within the range of the exida FMEDA results. The comparisons also show that, with two exceptions, the average FMEDA predictions for dangerous failure rates are only slightly less than those of the OREDA estimations. In those two exceptions, FMEDA predictions are higher than OREDA. Therefore, it is reasonable to conclude that, when compared in an “apples-to-apples” fashion, for the equipment analyzed in this paper, the exida FMEDA predictions and OREDA estimations are quite comparable.

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Yokogawa Electric Corporation (Yokogawa, President: Takashi Nishijima) announces that it has worked with the National Institute of Information and Communications Technology of Japan (NICT, President: Dr. Masao Sakauchi), Professor Yasuo Okabe of Kyoto University, and former Associate Professor Hiroki Takakura of Kyoto University to jointly develop a technology that visualizes and analyzes control system traffic to verify its integrity. This technology, which has been integrated by Yokogawa in an industry-first network healthiness check service, can quickly detect security incidents such as a malware infection. This combines visualization technology with the collection and analysis of traffic data to verify the integrity of control system networks, and is expected to improve the security of control systems used in public utilities.

Control system security has become a serious concern in recent years due to the proliferation of cyber-attacks targeting critically important infrastructure like public utilities: electric power, gas, and water. As control systems increasingly rely on operating systems and standard protocols that are both open and versatile, cyber attacks are very common now with various infection routes not only via the Internet but also via USB memory devices and other media, making it difficult to prevent all malware infections. Therefore, there is an urgent need for a technology that can quickly detect security incidents. Such technology should not have an impact on control system availability (stable, continuous operation) as these systems need to keep operating without interruption for very long periods, even as long as several decades.

NICT, Yokogawa, and Kyoto University jointly developed a technology for visualizing and analyzing control system traffic to verify its integrity and quickly detect security incidents such as malware infections.

Unlike general information systems where the amount and direction of traffic keep changing, it is easier with control system networks to identify when traffic conditions are normal as these systems are designed and used for a specific purpose. We focused on this characteristic. Our technology saves data on normal control system traffic conditions as a white list. With reference to this list, the technology monitors the dynamic state of the control system network to detect any abnormalities such as an increase in traffic or communication with an unknown IP address that could be caused by malware.

Furthermore, by using NIRVANA*, a real-time traffic visualization system developed by NICT, we improved this technology to comply with unique communications protocols used by control systems. As a result, this technology can identify traffic conditions much easier when an abnormality is identified (Figures 2 and 3).

Since there is no need to install detection software on each control system host (or server), this technology is easy to be introduced and does not impact control system availability.

Yokogawa Electric Corporation announces that Yokogawa Solution Service Corporation, a subsidiary that is responsible for Yokogawa's control business in Japan, has taken an order from Asahi Kasei Chemicals Corp. to provide a network healthiness check service that analyzes and verifies the integrity of the data traffic on the control system communications busses at its Mizushima Works. An industry first*, this cyber security service for control systems combines network visualization technology with the collection and analysis of data traffic.

As the threat of cyber-attacks has increased in recent years, there is an urgent need for strong security measures with control systems, particularly those used in critically important infrastructure such as electric power, gas, and petrochemical plants. With the increasing sophistication of such attacks, it is often no longer sufficient to rely solely on general security measures such as the use of antivirus software. Yokogawa's network healthiness check service is able to visualize the status of communications traffic on a network after periodically collecting and analyzing log data. When data traffic from an unknown IP address, communication via an unspecified protocol or port, data loss, or some other potential hazard is detected, Yokogawa will then work with the customer to identify possible causes and propose any necessary improvements. Unlike conventional services that rely on the monitoring and analysis of vast amounts of control system communications traffic, Yokogawa's service is able to quickly and intuitively visualize and grasp the status of the control system's communications traffic so that quick action can be taken in response to any potential issue. Yokogawa jointly developed this visualization technology with Yasuo Okabe, a professor at Kyoto University; Hiroki Takakura, formerly an associate professor at Kyoto University and currently a professor at the National Institute of Informatics; and the National Institute of Information and Communications Technology (NICT).

Yokogawa develops and provides to its customers a variety of highly secure device and system solutions, and is also engaged in the provision of ongoing operational support services. The company will continue to assist its customers through the provision of control system cyber security solutions.

Exida, a global supplier of functional safety products, services, and certifications has released their Safety Equipment Reliability Handbook (SERH) – 4th Edition, a hard copy of the SERH database with a vast amount of equipment item reliability data.

The SERH database provides a collection of failure rate data that is applicable for use in Safety Instrumented System (SIS) conceptual design verification in the process industry.

“The number of equipment items with realistic failure rate data has increased tremendously in the 12 years since the first edition was published,” says Rachel Amkreutz, SERH project manager. “The SERH remains the ultimate reference source for any safety engineer involved in Conceptual Design and Safety Integrity Level verification. Users of the information can trust that the data represented has been reviewed in detail and judged applicable for use to evaluate equipment items in Safety Instrumented Function (SIF) applications.”

“Having a single source of failure rate data, easy to implement by users in their SIL verification calculations, will improve effectiveness and consistency,” says Joe Scalia, ARC Advisory Group. “With the SERH, the amount of time needed to research individual products and determine the applicability of the data to Safety Instrumented Systems in the process industry, virtually drops to zero.”