Safety does not come out of a box

02/14/2014


Creating effective alarms

The move from panel board control to DCSs created the problem of alarm management, which spawned a whole new industry. In the old days when adding an alarm was an expensive process and took up valuable real estate on the wall or console, users took a great deal of care choosing those that were most important. Such is not the case anymore, and as we know, too many alarms make conditions worse for the operators and the plant.

Concepts of human software engineering suggest that alarm system design should ensure prompt, reliable, and effective operator response. A poorly designed system will leave an operator failing to act at all, or selecting the wrong course of action.

Today we have standards such as ISA18.2 and EEMUA 191 to guide users through the alarm lifecycle process, and most systems have built-in features to support assessing the current situation in a plant and identifying nuisance alarms and bad actors as part of rationalizing alarms.

State-based control is another methodology available to assist engineers while working through the design phase. By managing the parameters across process states, optimized process conditions can be maintained during normal conditions and correct action can be taken automatically during abnormal conditions. In this scenario, state-based control provides an additional layer of protection for the plant.

Integrated control and safety

Integrating control and safety systems can provide an enabling technology to drive effective operations and minimize the sources of human error discussed earlier. Some of those benefits include:

  • Analysis of potential common cause failures and designing those out of the system.
  • Standard access control to prevent unauthorized access and secure the systems without introducing additional custom programming.
  • Integrated testing at the product test lab rather than during a FAT (factory acceptance test) ensures all standard functions are working as the product was designed prior to market release. This reduces the scope of a FAT to project-specific requirements.
  • Version control, compatibility, and interoperability are all considered prior to the release of the product, reducing maintenance- and product-lifecycle costs.

Prescribing a solution does not address the need for analysis that is behind the performance based functional safety standards. It is our responsibility as users to design a system that effectively provides the required risk reduction and to verify that we have reduced the risk to an acceptable and reasonable level.

Security

Figure 4: The objective of a safety program might not be to eliminate risk entirely, but to reduce it to an acceptable level that will allow the plant to function while protecting people in the plant along with the community, environment, and equipment. CThere is no doubt that process safety and security are interconnected, and both should be given serious thought in the design process. Safety standards such as IEC 61511 do not restrict or prohibit combining control and safety; in fact, Part 2 indicates that “Physical separation between BPCS (basic process control system) and SIS may not be necessary provided independence is maintained, and the equipment arrangements and the procedures applied ensure the SIS will not be dangerously affected by failures of the BPCS or work carried out on the BPCS, for example, maintenance, operation or modification. Where procedures are necessary to ensure the SIS is not dangerously affected, the SIS designer will then need to specify the procedures to be applied.”

Having an integrated control and safety system with embedded access control not only provides security to the safety system and prevents unauthorized or unintended access, it also facilitates maintenance of the safety system with standard bypass or override methods.

These standard methods give the operator feedback of the condition in the safety system and are registered in the audit trail supporting best-in-class management of change.

Similar to safety systems, prescribing a security solution does not address the need for the analysis to ensure the automation infrastructure is free of known vulnerabilities and satisfies the needs of the industrial environment. Security deserves the same attention as safety as part of the cultural paradigm in manufacturing companies.

A two-sided effort

Reducing risk in a process manufacturing environment requires a technical and cultural effort. The most careful and conscientious people can be injured in a plant with faulty equipment, and the most sophisticated equipment can be defeated by careless people.

When careful people work with a safe attitude driven by a sound culture using well-maintained equipment and appropriate work practices, safe and reliable production will become a way of life. 

Luis Durán is product marketing manager for safety systems, control technologies, and process automation for ABB.

ONLINE

For more information, visit: www.abb.com

Read more about process safety below.

Key concepts:

  • Creating a safe working environment requires technical and human elements.
  • A corporate culture of safety has to be supported at all levels of a company.
  • Design elements in a control room can help or hinder the ability of operators to react in a crisis situation.

<< First < Previous 1 2 Next > Last >>

GABRIEL , CA, United States, 02/20/14 12:03 PM:

The article title got my attention and great opening statement. Good write up.
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2013 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
The true cost of lubrication: Three keys to consider when evaluating oils; Plant Engineering Lubrication Guide; 11 ways to protect bearing assets; Is lubrication part of your KPIs?
Contract maintenance: 5 ways to keep things humming while keeping an eye on costs; Pneumatic systems; Energy monitoring; The sixth 'S' is safety
Transport your data: Supply chain information critical to operational excellence; High-voltage faults; Portable cooling; Safety automation isn't automatic
Case Study Database

Case Study Database

Get more exposure for your case study by uploading it to the Plant Engineering case study database, where end-users can identify relevant solutions and explore what the experts are doing to effectively implement a variety of technology and productivity related projects.

These case studies provide examples of how knowledgeable solution providers have used technology, processes and people to create effective and successful implementations in real-world situations. Case studies can be completed by filling out a simple online form where you can outline the project title, abstract, and full story in 1500 words or less; upload photos, videos and a logo.

Click here to visit the Case Study Database and upload your case study.

Maintaining low data center PUE; Using eco mode in UPS systems; Commissioning electrical and power systems; Exploring dc power distribution alternatives
Synchronizing industrial Ethernet networks; Selecting protocol conversion gateways; Integrating HMIs with PLCs and PACs
Why manufacturers need to see energy in a different light: Current approaches to energy management yield quick savings, but leave plant managers searching for ways of improving on those early gains.

Annual Salary Survey

Participate in the 2013 Salary Survey

In a year when manufacturing continued to lead the economic rebound, it makes sense that plant manager bonuses rebounded. Plant Engineering’s annual Salary Survey shows both wages and bonuses rose in 2012 after a retreat the year before.

Average salary across all job titles for plant floor management rose 3.5% to $95,446, and bonus compensation jumped to $15,162, a 4.2% increase from the 2010 level and double the 2011 total, which showed a sharp drop in bonus.

2012 Salary Survey Analysis

2012 Salary Survey Results

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.