A maintenance record does not close a defect
A preventive-maintenance file is a stack of jobs: what was planned, who signed, sometimes a reading. A signed job shows the paper was closed. It does not show the plant is well, and it does not close a defect that needed a witnessed retest.
Ask what the job was allowed to prove. A filter changed, a torque checked, a lamp tested, a trend of a water sample filed. Each is a narrow sentence. A trend of iron in a pipe is not gas corrosion at a board, and it is not a pass of the cooling plant. A blank cell treated as normal is a missing observation. Say so, or the blank will be inherited.
Predictive sheets fail the same way if the point has no clock. A sample with no date, or a date that is the day the report was printed, is not a measurement time. Do not plot it as the week the plant changed. Do not paste the laboratory table into a public post. Their numbers stay in their file.
When a defect was found on a round and the maintenance record says completed, those are two documents. They agree only if the record names the defect and the evidence the original find required. A signature alone is not that evidence. The verification habit applies: the close is not lighter than the first test.
Original diagram. Not a work order.
From Run the Data Center Day, Tristan, Data Center Field Guides. No store link until the Kindle edition is listed.
Related: An open line is not a signature.
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