Archive for July, 2012

How much is enough?

The equipment is not in its normal condition and needs to be replaced now. . . or does it? Here is a situation that I see quite often and is addressed in this image. The warning in the limerick is not to overreact and deadline (or declare unfit for service) your vehicle just because it’s not in it’s normal condition. In this case, the graphic indicates that oil seepage from the wheel end bearings is “OK”, but “a streaky wet leak” is not.

I can’t count the number of times I’ve seen and heard of instances where all planned work for the shift was halted because something looked amiss and was immediately corrected. That isn’t to say that there aren’t good reasons to repair things immediately. The issue I’m exploring is whether certain conditions can be left alone and the repair can be scheduled to be completed at a later date. Do exact, defined conditions need to be stated? Can we trust the technicians that are operating and maintaining our equipment to know what is OK and what needs to be corrected immediately?

Early in my career, I believed strongly that taking all guesswork from the technician’s and operator’s control was the goal of any process or procedure. This was especially true when writing or reviewing Preventive Maintenance procedures or On-Condition inspections. As a result, I wrote job plans that were very specific and left little to interpretation, especially when something during the procedure was out of the ordinary. In my opinion, the clearer the steps were and the less the technicians had to think the better. As I’ve matured in my understanding of how maintenance programs operate best, I began to realize that there is a fine line between too much and too¬† little detail. Giving someone so much detail that you take away their ability to exercise their own good judgement disrespects them and makes them feel inferior. Leaving them with no idea of what the intent of the procedure is leads to misunderstandings and work that does not address the failure modes intended to mitigate. While I don’t think there’s a magic formula for how much detail is enough, I do think there are some general rules of thumb to keep in mind.

  • Use short sentences that get straight to the point.
  • Use “active” voice in a “positive” sense. “Verify switch is on”, not “Check switch is not off” or “Switch should be on”.
  • Do not use abbreviations or acronyms, especially industry-specific ones.
  • Put warning messages and notes BEFORE the step they reference.
  • Be specific about the range of values you’re interested in. Use the ends of the range, not nominal and plus/minus.
  • Don’t require calculations in the procedure.