A process requries a set of procedures. It means that you take actions to get results. The actions you take are your set of procedures (ISO).
A procedure is a high-level description that maps a process without getting into detailed instructions that describe how tasks within that procedure are carried out. Procedures talk about intputs/outputs, flow, measurements, etc. Work instructions should take someone through the steps that are necessary to complete a task or tasks for a responsibility in a procedure.
"A procedure describes how a process is performed, while a work instruction describes how a task is performed. Work instructions tend to be more detailed than procedures. Procedures can take the form of a narrative, a flow chart, a process map, or any other suitable form. Work instructions can also take any suitable form. However, one of the best ways to document a work instruction is to use a form. Forms are particularly useful because they become records once they're filled in."
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