Conducting a risk assessment is the first phase of the Safety Life Cycle, as defined in standards IEC 61508 and IEC 62061, which provides a detailed, systematic design process for machinery applications (See Figure 4). A risk assessment helps determine what potential hazards exist, and which safety mechanisms should be implemented to help ensure adequate protection. A risk assessment provides the basis for the overall risk reduction process, which involves the following steps:
- Reduce the risk of hazards by using inherently safe design concepts
- Employ safeguarding and protective measures with hard guarding and safety devices
- Implement complementary safety measures including personal protective equipment (PPE)
- Help achieve safer working practice with procedures, training and supervision
After a risk assessment, the designer will define the functional requirements of the machine and begin designing the safety system. The next step is to verify and validate the performance of the safety system design. The final phase in the life cycle is to conduct maintenance on the machine as needed and make future improvements as new technologies become available.
Investing in Advanced Safety Technologies
Traditionally, plants kept safety technology separate from their standard automation systems. Many manufacturers still embrace this approach and value employing workers whose main responsibility is to monitor and control safety systems.
However, this approach generally costs more and creates numerous design and integration issues.
The Aberdeen study found that although a majority of manufacturers continue to separate the two systems, 47 percent of the best-in-class are integrating. With many recent changes to safety standards and various advances in technology, many manufacturers find it increasingly easier to merge safety and standard control systems into a single platform, especially for discrete applications. One control platform minimizes the need to manage two disparate systems while lowering hardware, software and labor costs.
In addition to investing in single control platform technology, the study found adopting industrial Ethernet as the networking protocol to be a best-practice. Industrial Ethernet allows for a seamless transport of data between safety controls and standard control devices, allowing for increased visibility into safety data, among a slew of other advantages. The EtherNet/IP network, for example, allows users to effectively manage real-time control and information flow throughout the manufacturing and IT enterprise. By using a single, open protocol as the "networking backbone"f for the entire enterprise, users have the flexibility to control, configure and collect data from any point in the system to help simplify communications, improve productivity and protect manufacturing systems.
As safety standards and technologies continue to evolve, industrial plants with formal risk management programs in place are better equipped to keep up with safety compliance, and achieve superior operational performance. Forward-thinking manufacturers will work toward achieving or maintaining this best-in-class status by embracing a safety culture, creating a formalized risk management strategy and by investing in integrated safety technologies.
For more information on contemporary, integrated safety configurations, global standards, and how users are employing safety automation in their organizations, visit the Rockwell Automation Safety Resource Center: http://discover.rockwellautomation.com/safety.