A change can look minor to one discipline and significant to another. Moving equipment, altering a sequence or substituting a part may affect isolation, access or structural loading.
Change control creates a pause in which the right people can test those effects. The level of review should reflect the risk, with a clear record of the decision and any conditions attached.
The final step is communication. A controlled change is not complete until the crews, documents and equipment records all reflect the same arrangement.
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