All standards are not created equal: Read and implement with care
04/01/2003
By Mike Fitzpatrick and Ken Goldstein, Ph.D.
 Mike Fitzpatrick |
In several of our past columns, we've examined the details of specific cleanroom standards. This month, let's step back and take a look at the whole subject of standards and consider some of their strengths and weaknesses.
The advantages
 Ken Goldstein, Ph.D. |
Standards are often the first place we look when we are interested in the fundamentals. You've probably found yourself in a familiar rhythm: Want to know the specific definition of some industry terms? Check the standard. Want to know exactly what ISO Class 6 means? Look to the standard. Need to know the minimum requirements for testing the airborne particle concentration in a new facility designed to operate at a given airborne cleanliness level? You turn to the standard.
In each case, a standard is likely to be our starting point in understanding a particular subject. And while no standard will provide us with everything we need to know, it's essential that we consult the applicable standards before starting any cleanroom project.
We tend to use standards most when we are starting a new project, heading in a new direction, working with new groups, or building in a new location. Sometimes, as part of a postmortem analysis, we will go back and reread the standards when we are trying to figure out what went wrong. And even when things go well, effective organizations often go back to formally review projects to identify strengths and weaknesses and to recognize those areas needing improvement.
Standards give everyone a common starting point and provide a means of communicating. When we say that we have an "ISO Class 5 facility," people understand what we mean—ISO Class 5 facility means exactly the same thing regardless of the location, nationality, local language or manufacturing process involved.
Without standards, we would evolve into a technical Tower of Babel. Where would we be if we did not have a universally understood definition of "ISO Class 5," "unidirectional," "airborne particle" or any of the other bits of jargon that we regularly use? We would soon be reduced to the level of clothing manufacturers, where the same pair of men's shoes in Japan is size 27.5, size 9.5 in the U.S., 9 in the UK and size 43 in the remainder of Europe.
Standards also save us time. In technical discussion or debate, they serve as our shorthand. Any participant can point to a particular section in the standard and others will nod, at least knowingly, if not approvingly.
Finally, many of today's standards are the result of international standards setting bodies that foster communication between widely varying groups. Commercial transactions can be simplified and free trade encouraged by employing standards.
The disadvantages
However, in rapidly advancing technologies, standards can become outdated faster than they can be revised. And if the critical terms are too narrowly defined, users will tend to create their own terms and definitions.
This was the case with Federal Standard 209E where many microelectronics facilities were considerably cleaner than the cleanest class defined in 209E, Class 1. These facilities operated "off-scale" on the clean end of the curve and their owners were obliged to concoct creative and frequently obtuse "classifications" to describe them.
While these "classifications" have had a specific meaning to those who created them, the terminology remained undefined outside of the immediate user group and, therefore, was of little use when trying to communicate with others.
Frequently, we will misuse standards in our quest for the "magic number." This occurs when instead of actually defining and solving a problem (too expensive and time-consuming), we reach for a standard and try to use it like a cookbook. Forget about wading through all 28 pages of the standard—that will only be confusing.
Standards cut both ways, and if improperly written or applied, can be used to retard or even freeze technological development. They may be misused to obtain unfair commercial advantage and restrain free trade.
Remember that standards are not created equal. They span all degrees of technical quality. The standard setting bodies writing the documents are not omniscient and frequently go off on a tangent. This is not altogether unexpected considering the diverse make-up of these groups and the difficulty they experience in obtaining individuals willing to participate.
Choose your standards with care, read them carefully, use them appropriately, and if you see a standard that needs to be improved, participate in the group that writes the standard.
Michael A. Fitzpatrick is program director of microelectronics for Lockwood Greene. A senior member of the Institute of Environmental Sciences and Technology (IEST), he is chairman for WG012 (Considerations in Cleanroom Design) and WG028 (Minienvironments). He can be reached at [email protected]. Ken Goldstein is principal of Cleanroom Consultants Inc. in Phoenix, Ariz., and is a member of the CleanRooms Editorial Advisory Board. He can be reached at [email protected].