One of the goals of the ISO 9000 Quality Management System standard is to bring control and consistency to your processes. The year 2000 revision of the standard asks you to identify your key processes, and manage and improve those processes. Documentation is one of the ways you manage and control your processes. By writing procedures and work instructions you will make sure that everyone is performing the process the same way.

ISO 9000 documentation comprises four tiers. Each tier should point to the next.

1. The Quality Manual
   Your quality manual briefly describes how you meet the requirements of the standard via the system you implemented. Write this document last. It will be hard to write it before you implement your system, and it will have to be rewritten as you fine-tune your system. If you write the quality manual at the end of your project it will be a simple summary of what you have implemented for each clause. Your quality manual must include or reference your procedures.
   
2. Procedures
   Procedures describe how to perform a task in general, outlining the key steps and their order. A purchasing procedure may describe who is responsible for approving purchases, and what records need to be kept, for example. Procedures can be described as looking at "what" you do (not necessarily how you do it). Procedures should reference related work instructions.
   
3. Work Instructions
   Work instructions provide detailed step-by-step descriptions of a task, not just an outline. They should describe "how" you perform a task. A purchase order work instruction would tell you how to fill out a purchase order, line by line. Work instructions should reference related records.
   
4. Records
   Records are the documents you keep to show that you follow your quality system. Your completed purchase order would be a record. Records are a history of what has occurred and as such should not change.

Note: Write your documents in present tense. Something "is" done not "should be". It is a much stronger statement and removes some ambiguity. Try not to use "where appropriate", "when needed" or other phrase that makes the document less clear.

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