Write a Master SOP


In quality management it is important that you do what you say and say what you do. By recording all the major processes in the laboratory in Standard Operating Procedures (SOPs) you assure that these processes are carried out in exactly the same way every time, which means that you have standardized the process. As the SOPs need to be reviewed and authorized by different persons to check correctness, you also assure the quality of the procedures in those SOPs.

To make sure that all the SOPs in the laboratory are written in the same way and are complete you need a Master SOP that explains exactly how an SOP must be written.

Find more information on documents, records and SOPs in the WHO Laboratory Quality Management System (LQMS) handbook documents provided in the right-hand column.


Start with writing a Master SOP. In this document you explain exactly which types of SOPs exist, what the outline is of each type of SOP and how the SOPs must be written.

Different types of SOPs

In this tool we distinguish between three types of SOPs:

  • Equipment SOPs
    These are SOPs on how to calibrate, operate and maintain equipment. For every piece of equipment an SOP must be written on how to calibrate, use and maintain that piece of equipment.
  • Analysis SOPs
    These are SOPs on how to perform an examination. For every examination an SOP must be written explaining how to make the reagents, how to prepare the sample, how to perform the examination and how to perform the quality controls.
  • Procedure SOPs
    The majority of the SOPs you will have to write will fall in this category. A Procedure SOP is written for any procedure in the laboratory. This can range from collecting the patient sample to cleaning of laboratory rooms to performing the management review.

Include in the Master SOP specific sections on how to write SOPs for each category. In the right-hand column three information sheets are given that provide the outline and details of SOPs of each category.

General SOP outline

An SOP generally consists of the following elements:

  • The title of the SOP
  • The objectives and scope of the SOP
  • The abbreviations, definitions, and terms used in the SOP
  • The tasks, responsibilities and accountabilities in the procedure the SOP is written for
  • Safety and environment
    The measures that need to be taken to protect the safety and environment.
  • The procedure
    Divided over the sections:
    • Materials and Reagents
    • Procedure
    • Quality Control

  • The documents related to the SOP
  • The forms related to the SOP
  • The references
  • The appendixes
    Appendixes can include forms, additional instructions, manufacturer manuals, checklists, etc.

For Equipment SOPs generally a section is added describing the method for calibration and for maintenance, divided into preventive and corrective maintenance procedures.

SOP Coding

To keep oversight, all SOPs need to be coded. Which system you use for coding has to be decided by you. However, we provide one example of a coding system that you could use:
One part of the code on SOPs indicates the group to which a document belongs, which number the document has in this group, and another part indicates the version number of the document. An example may best illustrate this:

  • The code of the AFB Smear Microscopy SOP is A04v03:
    • The SOP describing AFB Smear Microscopy is an Analysis SOP, this is indicated by the "A".
    • It is the fourth SOP in the group of Analysis SOPs: "A04"
    • As the SOP has been revised twice, the current version of this SOP is number 3: "A04v03".
  • The code of the centrifuge SOP is E06v02:
    • The SOP describing Use and Maintenance of the Centrifuge is an Equipment SOP, this is indicated by the "E".
    • It is the sixth SOP in the group of Equipment SOPs: "E06".
    • It has been revised once, thus the current version is version 2: "E06v02".

In the right-hand column a template Master SOP is provided that can be used both as example and as template for making your own Master SOP. It is important that you make your own SOP and not literally copy the template SOP. An SOP is specific for the organization as it documents exactly the procedure of how it is performed in your laboratory. When you copy the template SOP it will not describe exactly the procedure of how it takes place at your laboratory, hence it is useless.

How & who

Quality Project Team (including the Laboratory Manager):

  1. A document with general background information on documents and records of the WHO Laboratory Quality Management System (LQMS) training is provided in the right-hand column. Read this first.
  2. A document with background information on SOP writing of the WHO LQMS training is also provided. Read this as well.
  3. Read the template Master SOP provided in the right-hand column. This gives you an idea of how it should be written and how SOPs are made in general.
  4. Make a rough overview of what you want to describe in the Master SOP.
  5. Write the Master SOP.
  6. Let members of the Quality Project Team (that have not helped in writing the Master SOP) read the document and ask for suggestions for improvement.
  7. Improve the document.
  8. Print the final version of the Master SOP.
  9. Take a new folder and name this "Procedure SOPs". Put the Master SOP in this folder.
  10. Staff members have to read the SOP so that they also know what an SOP is and which elements it consists of. It is important that you can track who has read the SOP and who not. To track whether the staff members have read the SOPs, a Read and Understand List must be used. In the right-hand column a template of such a list is provided. Insert the names of all the laboratory staff members (if necessary add extra columns). Add the titles of the SOPs to the left column. Cross the cells of the staff members that do not have to read a specific document. For clarity´s sake an example of a Read and Understand List with signatures and crossed cells is provided as well. In this example you also see cells without signatures. This means that the staff members with empty cells in their column have not yet read the document in the row of these cells.
  11. Place the Read and Understand list at a location that is visible for all staff members such as a notice board.
  12. Present the Master SOP to all staff members in a weekly staff meeting and explain that all the SOPs must be written according to the procedure described in the Master SOP. Stress that everybody must read the Master SOP and, when they have read it, must sign the Read and Understand List. Explain where to find the Master SOP and the Read and Understand List.
  13. Regularly check if every staff member has read the list. If not, motivate the staff members who have not yet signed the list to read the SOP.

Back to Roadmap Activity Overview
This activity belongs to the QSE Documents & Records
ISO15189:2007: 5.5.3
ISO15189:2012: 5.5.3