So now do we get to start writing an SOP? Not exactly. Anyone can sit down and write steps in a procedure, but the person who outlines and gets the big picture will write an SOP that will really work.

They say that a picture is worth a thousand words. If that is true then a flowchart must be worth a thousand procedures. Flowcharting can be an invaluable tool for understanding the inner workings of a process or activity to be performed. So what is a flowchart you ask? Flowcharting is a method of graphically describing an existing process or a proposed process by using simple symbols, lines, and words to display pictorially the activities and sequence in a process. Flowcharts graphically represent the activities that make up a process much like a map represents an area of land.

Flowcharts are very useful when a process has many decisions or steps. Flowcharts can also take a complex process and break it into several simple steps. As a rule of thumb if you see more than three to five decision blocks in the flowchart consider breaking the SOP into separate documents. Flowcharts come in very handy when quick decisions or actions are needed and reading a textual style SOP is not an option. This is particularly true in emergency or critical situations such as in response to a spill or other lab emergencies.

One of the big disadvantages of flowcharts is they take time to create and maintain. Flowcharts are most helpful when defining a new process or procedure. As time goes on either the text or the flowchart become out of date. This of course opens the organization up to questions during audits and inspections. A common practice is once an SOP has matured (i.e. people are using it without any problems) consider removing either the flowchart or the text. Another disadvantage is that because they are pictorial representations of a process and you can only get so much information on an 8 ½” by 11” sheet of paper, flowcharts often contain minimal detail. And as we all know, the devil is in the details. Therefore, most flowcharts are supported by text which does contain the details.

Although flowchart symbol standards exist (i.e. ISO, ANSI) people deviate form these standards to suit their own needs. In many cases, individual companies develop standards for their internal use. Below are the five most commonly recognized symbols used in flowcharting:

  1. Rectangle for a process or activity,
  2. Diamond for decisions,
  3. Oval for starting or ending a process,
  4. Line with arrow showing the direction of the flow, and
  5. Small circle which act as a connector to other flowcharts or sheets.


Another common symbol used in SOPs is the document symbol that shows the need to use another SOP or the requirement to complete a form, or create a record. The simple flowchart in Figure 1 shows use of all the symbols except the small circle. If the”How to Pipette” process led to another process or more detail was shown the small circle (with the connector letter in it e.g., A, B, C…) might be needed.

Look closely at how the sample SOP is laid out. Did you see the outline of the SOP? By dividing the flowchart into three logical major headings: 1) Prepare Pipette, 2) Take Sample, and 3) Transfer Sample, the structure of the written portion of the SOP beginnings to take shape. Figure 2 shows what the “How to Pipette” SOP outline might look like.

Wouldn’t you agree that this is a pretty easy method for drafting an SOP? There is a lot more that can be said about creating and using flowcharts. A couple of references are provided below but a web search on flowcharts will yield a wide range of material. Also to make the creating and maintaining of flowcharts easier, there are plenty of flowcharting tools available but that’s a topic for another time.

Now we’ve worked through one method for drafting your SOP. Next time we’ll look at a rather unique drafting method called mind mapping.


  1. American National Standard, ANSI X3.6-1970, Flowchart Symbols and their Usage in Information Processing
  2. Harrington, H.J., Business Process Improvement, McGraw-Hill, 1991
  4. International Organization for Standardization (ISO), ISO 5807:1985 Information processing — Documentation symbols and conventions; program and system flowchart.


Sample Flowchart
Figure 1. Sample Flowchart

Sample Outline
Figure 2. Sample Outline from Flowchart


Norm Moreau is a consultant and trainer known for developing SOPs and implementing SOP programs that demonstrate GLP/GMP and nuclear QA compliance. His products and services are used to achieve ISO 9001 registration and ISO 17025 accreditation or by organizations that simply want to improve their operational efficiency and effectiveness. Since 2000, Norm has been offering the Writing SOPs that Work workshop at the National Meetings of the American Association for Laboratory Animal Science (AALAS). He welcomes comments, questions, even criticisms and can be reached at