Getting It Write? - - Chromatography Online
Getting It Write?

LCGC Europe
Volume 25, Issue 11, pp. 630-639

Lessons Learnt

Table 1: Sections and contents of a standard operating procedure (SOP).
The key point is that to be effective, procedures have to be read, understood and followed. Therefore less is very much more. Simple procedures that are understandable are the key. A procedure that is unreadable, complex or not followed is worse than no procedure at all. The reason for this is that a laboratory understands the need for written procedures but has implemented them in a way that makes them impossible to follow, defeating the purpose of the procedure. The problem is that you'll get kicked if you don't have a procedure, but kicked twice as hard if you have a procedure but don't follow it.

Writing a Procedure is a Pain

The problem with writing or updating procedures is that it is a task that is usually classified in the same category as watching paint dry. It is a pain in which ever part of your anatomy you wish to choose and it is perceived by many as a boring but necessary job to do. Typically it is perceived as a job inflicted upon the innocent analysts of the laboratory by those people who inhabit the evil planet of Quality Assurance.

This is one end of the Gaussian distribution of analytical scientists working in the laboratory. Interestingly, these are the people who play the starring roles in quality audits and regulatory inspections by providing the ammunition to the auditors and inspectors to write their nonconformances or non-compliances respectively. Perhaps it is worth reminding people with this attitude that the words above Traitor's Gate at the Tower of London "Abandon All Hope Ye Who Enter Here" should be written above the entrance to your laboratory?

Writing a Procedure is a Business Benefit

At the other end of the Gaussian distribution are the analytical scientists who view written procedures as a benefit to a laboratory. Within a quality system, regardless of the standard or regulation you follow, there is a single set of requirements or rules that you have to follow; however, there is room for interpretation.

Therefore all laboratories are the same — except for the differences.

However, it is the differences that cause the problem. After all how do you train new recruits, even from within the same industry or quality system, in how you work — by thought transference perhaps? Hence the importance of effective, well written and presented SOPs. Put simply, the procedures describe how you work in your laboratory.

Essential Elements of a Written Procedure

Table 2: Using white space in a written procedure.
What should be in an SOP or written procedure? Table 1 presents the main sections that should be in a procedure that, inevitably, will vary from company to company but most have these sections with differing order. The purpose and scope sections should be fairly brief and outline why the procedure has been written and what it contains. As we are discussing a description of an analytical process, key words and abbreviations should be defined, although a simpler alternative is to have a technical glossary for the whole laboratory which is simply crossreferenced within each procedure. A technical glossary is an easier and more elegant way to define technical terms and abbreviations, and can even be sub-divided into general analytical and technique specific terms and abbreviations in a single location which is easier to maintain.

At the bottom of the table is the references section and this is where there can be differences, as some organizations will not put these into a procedure and others will. I am puzzled by the former attitude as most laboratories who do not cross reference other documents say it is to prevent an auditor or inspector from asking for other procedures. The main problem with this approach is that one of the first items asked for at the start of an audit is a list of SOPs that the laboratory has which rather defeats the laboratory argument.

As we are discussing procedures in an analytical laboratory, procedures related to the preparation of reagents and analytical reference standards will be involved. If not defined elsewhere, the way of preparing these needs to be stated in the procedure including a statement of the tolerances or ranges of critical standards. For example, it is unlikely that you will be able to weigh 20.0 mg of an analytical reference standard or a sample consistently, so the procedure should define what is acceptable e.g. between 19.8 – 20.2 mg.

The main sections that I want to focus on in this article are the heart of any procedure: responsibilities and the procedure itself.

Know and Understand the Laboratory Process

Any procedure is written for a defined and repeated process, not a one-off activity. Therefore, the key to writing an SOP is knowing and understanding the process that you are going to document. Sounds simple doesn't it? You would be amazed at the number of people who attempt to write a procedure without this knowledge. Therefore you need an analytical scientist who is involved with the process: in the current technical jargon this individual is called a subject matter expert or SME.

From the scope of the procedure, the boundaries of the procedure are defined along with the inputs (what do you need to start) and the outputs (what you end up with at the finish). Along the way there may be sample storage, preparation, analytical instrument set up, analysis and data recording, interpretation of the data, calculation of results and reporting. What is covered by this specific procedure needs to be defined, and you need a person who understands what is going on.

Who Is Involved And What Do They Do?

The traditional way of writing a procedure is to consider the roles and the responsibilities of those analytical staff that will be using it. We need to consider:

  • Who is involved?
  • What do they do at each stage of the process?

Where there are hand-offs from one individual to another, this is where user problems could occur and there is a need to define carefully which tasks must be completed by one individual, and what must be passed onto another (in terms of documentation and any records such as data files etc). One way to ensure that this transfer is complete is to use a checklist or a proforma document although in regulated laboratories any pro-forma documents need to be formally issued and controlled. The other consideration is that most analytical work uses the four eyes principle: one person to perform the work and another one to review and approve it. It is important that one of the responsibilities of the performer is to ensure that the work package handed over for review is complete from the tester's perspective. Glaring errors need to be trapped by the tester and not left for the reviewer to spot.


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