A maintenance SOP (standard operating procedure) is a detailed document that describes all the steps maintenance workers need to follow while performing a task. It explicitly defines the expected practices and quality standards that need to be met.

A standard maintenance procedure is a detailed list of steps that describes how to perform a maintenance task and is also a documented standard to which the job or task should be performed. All repetitive maintenance tasks should be covered by SMPs, regardless of who performs those tasks, be they craftspeople, contractors or operators.