What happens when two experienced employees perform the same critical task in completely different ways?
In a small, low-risk operation, the differences may not matter much. In a pharmaceutical laboratory, aircraft maintenance facility, food production plant, or medical device company, they can have serious consequences.
This is where standard operating procedures, commonly known as SOPs, become important.
An SOP turns organisational knowledge into a repeatable process. It establishes how work should be performed, who is responsible, where the procedure applies, and what records should be created.
Yet having more procedures does not automatically create a better organisation. An SOP that is unclear, outdated, unnecessarily complicated, or disconnected from actual work can become another source of error.
The real challenge is creating procedures that people can actually follow.
Why Experience Alone Is Not Enough
Experienced employees often develop efficient ways of performing their work.
That experience is valuable, but relying entirely on individual knowledge creates a problem.
What happens when that person leaves?
Imagine a technician who has calibrated a particular piece of equipment for ten years. The technician understands its quirks, knows which measurements require additional attention, and recognises early signs that something is wrong.
If those practices exist only in that person’s memory, the organisation has a single point of failure.
SOPs help convert individual knowledge into organisational knowledge.
This does not mean every movement or decision needs to be documented. Instead, important activities should be defined clearly enough that another appropriately trained person can reproduce the process consistently.
Laboratories: Consistency Determines Whether Results Can Be Trusted
Laboratories provide one of the clearest examples of why standardisation matters.
Suppose two technicians receive identical samples.
One allows the samples to reach room temperature before testing. The other begins immediately. One calibrates the equipment at the start of the day, while another assumes yesterday’s calibration remains sufficient.
Could these differences affect the results?
Depending on the test, absolutely.
A laboratory procedure can define sample preparation, equipment requirements, environmental conditions, measurement methods, acceptance criteria, and documentation expectations.
The objective is not simply to make everyone work identically for the sake of uniformity. It is to reduce unnecessary variability that could influence the result.
When a result falls outside expectations, documented procedures also make investigations easier. Teams can determine what should have happened and compare that with what actually happened.
Without a defined process, identifying the deviation becomes considerably harder.
Aviation: Procedures Protect Against Routine Becoming Casual
Aviation maintenance involves highly trained professionals performing tasks they may have completed hundreds of times before.
That experience does not eliminate the need for procedures.
In fact, familiarity can introduce its own risks.
A task that has been performed successfully many times can begin to feel routine. Steps may appear obvious. Checks may feel unnecessary. Small shortcuts can gradually become normal practice.
Procedures create a common reference point.
For example, replacing an aircraft component may require specific preparation, inspection, torque settings, testing, and documentation. The technician’s experience helps them perform the work efficiently, but the approved procedure establishes the expected process.
This distinction matters in industries where “I’ve always done it this way” is not sufficient evidence that the process is correct.
Food Manufacturing: The Same Product Must Be Made Safely Every Time
Food production presents a different type of repeatability challenge.
A manufacturer may produce thousands of units every hour across different shifts, production lines, and facilities.
The customer expects essentially the same product every time.
More importantly, the product must remain safe.
Procedures can govern cleaning, allergen control, ingredient handling, temperature monitoring, equipment setup, contamination prevention, packaging, and product release.
Consider cleaning between products containing different allergens.
If one operator follows a thorough cleaning process while another relies on visual inspection, the difference could create a serious problem.
A documented procedure establishes what cleaning means in practical terms.
What equipment must be cleaned? Which cleaning agents are used? How long should the process take? Is verification required before production resumes?
These details turn a vague instruction such as “clean the production line” into a reproducible process.
Medical Devices: SOPs Are Part of the Quality System
Medical device organisations face the same need for consistency, but there is an additional consideration: many procedures also form part of the organisation’s formal quality management system.
Activities such as risk management, design and development, document control, complaints handling, production, supplier management, corrective actions, and internal audits need to operate in a controlled manner.
This is why understanding the purpose and scope of SOPs in a quality management system matters. A procedure should make clear why it exists and where it applies rather than simply collecting instructions under a document number. Medical Device HQ notes that a well-defined purpose can address the expected output, the wider objective of the process, regulatory requirements, consistency, and efficiency.
Take medical device risk assessment as an example.
An organisation might employ several engineers who are all capable of evaluating risk. But if every engineer uses different terminology, different criteria, or different documentation methods, combining and reviewing their work becomes unnecessarily difficult.
A procedure establishes the organisation’s agreed method.
Importantly, this does not mean the SOP should attempt to replace professional competence. A procedure can explain how risk assessment is performed within the organisation, but employees still need the knowledge necessary to make appropriate technical judgments.
The strongest quality systems use procedures to support competent people, not to compensate for the absence of competence.
Cybersecurity Teams Need Procedures Too
SOPs are not limited to traditional manufacturing or heavily regulated physical products.
Consider cybersecurity incident response.
When suspicious activity is detected, the organisation may need to determine whether an account has been compromised, isolate affected systems, preserve evidence, notify appropriate personnel, investigate the incident, and restore normal operations.
This is not the ideal moment to decide who should do what.
An incident-response procedure establishes responsibilities before the crisis occurs.
The same applies to backups, access control, vulnerability management, software deployment, and disaster recovery.
Technology may automate parts of these processes, but organisations still need agreed methods for handling exceptions and making decisions when automated systems cannot resolve the situation themselves.
A Procedure Can Be Too Detailed
If SOPs are useful, should every activity be documented step by step?
Not necessarily.
Excessive detail can make a procedure difficult to maintain and frustrating to use.
Imagine an SOP that tells an experienced laboratory technician exactly how to open a software application, including every mouse click. A minor interface update could make several pages obsolete overnight.
At the other extreme, an instruction such as “perform the appropriate analysis” may provide almost no useful guidance.
The appropriate level of detail depends on the activity, the competence of the user, the complexity of the task, and the consequences of performing it incorrectly.
A good SOP provides enough structure to achieve consistency without attempting to document every obvious action.
Purpose and Scope Prevent Confusion
Two of the most useful parts of an SOP are also among the simplest: purpose and scope.
The purpose answers: why does this procedure exist?
The scope answers: where, when, and to whom does it apply?
Confusing the two can create surprisingly unclear procedures.
Suppose a company writes:
“The purpose of this procedure is to cover supplier evaluation and monitoring.”
That describes what the document contains, but not necessarily why the process exists.
A stronger purpose might focus on ensuring that suppliers consistently provide products or services meeting defined requirements.
Scope can then establish which suppliers, products, departments, or lifecycle stages are covered.
This distinction helps employees understand not only what the procedure says but also the result it is intended to achieve.
Procedures Must Match Reality
One of the biggest SOP problems occurs when the documented process and the actual process become different.
Perhaps the procedure was written years ago.
The company has since introduced new software, reorganised departments, changed equipment, or developed more efficient working methods. Employees gradually adapt, while the controlled document remains unchanged.
Eventually, an auditor or internal investigation compares the procedure with actual practice and discovers that they no longer match.
Which one is wrong?
Potentially both.
Employees should follow approved processes, but organisations also need mechanisms for improving procedures when better methods emerge.
An SOP should therefore be controlled without becoming untouchable.
If people repeatedly need to work around a procedure to complete their jobs, the organisation should investigate why rather than simply telling employees to follow it more carefully.
Training Determines Whether Procedures Work
Publishing an SOP does not mean people understand it.
Employees need to know which procedures apply to their work and what has changed when procedures are revised.
Training does not always need to mean a classroom course.
A minor update may require employees to review the revised section. A complex new manufacturing process may require theoretical instruction, demonstration, supervised practice, and evidence of competence.
The training method should reflect the significance of the activity.
This also highlights an important distinction between reading and competence.
Someone can sign a record confirming that they have read a procedure without being capable of performing the task correctly.
For critical activities, organisations may need to verify that employees can actually apply what the procedure requires.
SOPs Should Improve Work, Not Just Satisfy Auditors
Procedures are sometimes treated primarily as compliance documents.
That misses much of their value.
A good SOP reduces ambiguity. It makes onboarding easier. It preserves knowledge when experienced employees leave. It helps different teams perform the same process consistently. It provides a baseline for investigating deviations and identifying improvements.
Most importantly, it makes the organisation less dependent on informal knowledge.
The objective should not be to create a procedure for every possible activity.
It should be to identify where consistency matters and document those processes well enough that competent people can perform them reliably.
Whether the organisation manufactures food, maintains aircraft, responds to cyber incidents, operates a laboratory, or develops medical devices, the underlying principle is similar.
Important work should not depend entirely on someone remembering how it was done last time.
