15 June 2015

Under-specifying - less is not always more

Singing Ringing Tree. A 3-metre tall
structure of stacked galvanized steel pipes.
(c) David Dixon
One of my favorite tales I use when teaching about specifications happened to me shortly after I took my first job as a specifier, at the University of Minnesota. Prior to taking this job, the sum total of my experience with specifications consisted of copying specifications onto drawing sheets. This activity was presented to me as little more than a mindless job, a necessary evil that was to be done as quickly as possible, with no explanation of what specifications are. As you might expect, there was no mention of CSI, MasterFormat, or SectionFormat.

This seminal event in my life as a specifier took place within a few weeks of starting my new job. It started with a phone call from one of the construction administrators.

"The contractor wants to know what kind of pipe we want for the bollards."

I didn't know, but I was sure it was in the specifications, so I responded, "It's in the specs, isn't it?" (Brilliant, don't you think?)

"It is, but the contractor says he needs to know more."

At this point, I'd like to commend the contractor for asking the question. It would have been entirely correct for the contractor to provide anything that complied with the specifications, but as we'll see, that could have create just a bit of a problem. Instead, the question was asked, and I learned a most valuable lesson about reference standards.

I don’t recall exactly what our specifications said, but it wasn't much more than "Bollards: ASTM A53." Apparently, that wasn't enough. Because of my lack of familiarity with specifications, I didn't know why, but I was bound to find out.

I found a copy of ASTM A53, and the title - Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded, and Seamless - immediately made it clear that I was in trouble. ASTM A53 doesn't cover just one type of pipe, but several: It could be black or galvanized, and it could be seamless or welded.

Looking further, I discovered that welded pipe could be either furnace-welded or electric-welded, and that seamless pipe had two Grades. No wonder the contractor was confused!

My education didn't stop there. The standard has several appendices, one of which is a four-page table of combinations of dimensions, weights, and test pressures for plain end pipe. There is a similar table for threaded pipe, and a few other tables of properties for good measure.

As noted, I'm glad the contractor asked the question, for a couple of reasons. It's too easy to complain about contractors, and blame them for everything that goes wrong. In truth, they often do things as they should be done even when they are not clearly described in the contract documents, and sometimes when they aren't there at all.

The other reason is that this problem was a great introduction to the proper use of reference standards. At the time of this misadventure, I think I had heard of CSI, but had not yet joined the local chapter; it was to be still longer before I studied for the CDT/CCS exam, where I would have learned about reference standards.

Lessons learned from books and teachers are valuable, but they are no substitute for lessons learned in the School of Hard Knocks.

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