This article was printed in CONTROL's November 2009 edition.
Standard implementation is like exercise and eating right. No one is opposed to the idea in principle, but many don't follow through in practice. Let's look at the benefits of standards, then examine implementation issues. "Standards help an organization manage risk when adapting new technology," says Marcus Tennant, principal systems architect, Yokogawa IA Global Marketing. "An automation standard makes it easier to justify new technology because others have walked the same path. Examples include adapting a batch execution package based on ISA88, a B2MML implementation based on ISA95, or an alarm management solution based on ISA18."
"Life-cycle costs will be reduced due to modularization and flexibility of systems that follow standards. There will be less dependence on a proprietary solution, architecture or individuals. When standards are followed, it's much easier for others to understand the system and make changes," continues Tennant.
"Finally, standards help companies transfer knowledge on a global basis more easily, and encourage inter-company communications. Standards improve consistency and repeatability, enabling reduced design and engineering costs. ISA88 demonstrated order of magnitude reductions in engineering costs compared with previous methodologies," concludes Tennant.
A system integrator details other benefits. "With standards, existing program libraries can be reused," says Michael McEnery, PE, president of McEnery Automation in St. Louis and vice chairman of the WBF (www.wbf.org) standards organization. "Many tough decisions will have been made and will be contained in the standard. Applications and sites within an organization will be consistent. And, management, IT and engineering will see eye-to-eye, " adds McEnery.
Benefits are many, but caveat emptor. "The benefits of implementing control system industry standards are easy to rattle off during a presentation by a software salesman, a standards committee spokesperson or a trade journal writer. But, the question is: do the benefits outweigh the costs? Typically the answer is yes, but it's not always a slam dunk," McEnery says.
"Standards are not a set of hard-and-fast rules or step-by-step instructions. They are guidelines that provide enough flexibility to be applied to a wide variety of applications," explains McEnery. "Extra effort and cost are required to understand standards, and determine how they should be applied in your unique situation. Standards implementation expenditures should be more than offset by savings from applying work already done for you by industry experts, software developers and system integrators. However, implementing standards means changing the status quo. This requires extra effort in planning, training and support, and it's difficult if everyone isn't on board."
In addition, notes Tennant, "When an organization is considering a standard, there are individuals who may perceive that their jobs or careers are being threatened."
McEnery adds, "Programmers are creative types, and may feel limited by having to follow a standard. Having them understand the goals and benefits of standards can mitigate these feelings, but keep in mind that some programmers think job security is tied to developing programs that only they can understand."
Now that we understand the benefits and challenges of standards, we can look at best practices for implementation. "Standard implementation requires training, and this means more than reading the standards document, checking out a website, or taking a prepackaged class. You need to find examples of standards implementation in a process control situation similar to yours," recommends McEnery. "Find a technical organization involved in standards, such as WBF or WINA, and attend presentations to get first-hand advice from experts for little or no money. The cost will be a drop in the bucket compared to money saved as a result of a well-implemented standard."