SOP Industrial: What it is, how to implement it in your industrial plant | Guide 2026

What is a SOP and why should you care?

A SOP (Standard Operating Procedure) or standard operating procedure is a document that describes step by step how to perform a specific task within an organization. In the industrial context, a SOP defines exactly how to operate a machine, execute a production process, make a format change or act upon an incident.

The definition is simple. What is not simple is the reality of the majority of Spanish industrial SMEs: only 23% have documented and updated operating procedures. The remaining 77% depends on what the expert operator has in his head — what in English is called "tribal knowledge" or tacit knowledge.

This means that when that person leaves, retires or changes companies, the knowledge goes with them.

SOP vs work instructions vs operations manual

There is frequent confusion between these three concepts. The difference is one of scope:

• Operations manual: general document that describes the overall functioning of a plant or department. It is rarely consulted on a day-to-day basis.
• Standard Operating Procedure (SOP): describes a complete process from start to finish — for example, “packaging line start-up.” It includes the steps, the order, the quality criteria and what to do if something goes wrong.
• Work instruction: describes a specific task within a SOP — for example, "set head pressure to 2.5 bar". It's more granular.

For an industrial SME, the most practical thing is to work at the SOP level: complete processes that an operator can follow from start to finish. If within a step you need more detail, you add the work instruction as a sub-step.

Why industrial SMEs need SOPs (with data)

Data from the Spanish industrial sector are clear about the cost of not having documented procedures:

Without SOPs, every loss is a crisis. Each incorporation is a double cost (the new one does not produce, and neither does the tutor). Every retirement is an irreversible loss of knowledge.

With SOPs documented and accessible, knowledge stops depending on people and becomes an asset of the company.

The 5 most common types of SOP in industrial plants

Not all processes need a SOP. Start with the ones that have the most impact:

1. Machine start and stop: the processes that have the most variability between operators and that generate the most errors when executed by someone other than the owner.
2. Change of format or product: where an error in the parameters generates rejections of entire batches. They are the SOPs with the highest immediate ROI.
3. First level preventive maintenance: the tasks that the operator must do before each shift and that many skip because they "already know" how to do them.
4. Incident management: what to do when the machine fails, what to check before calling the technician, when to stop production. Troubleshooting that avoids unnecessary stops.
5. Security protocols: lockout/tagout procedures (LOTO), use of EPIs, emergency response. They are required by regulations but are rarely updated.

How to create an industrial SOP in 5 steps

1. Identify critical processes

Do not document everything at once. Start with processes that meet at least one of these criteria: only one person knows how to do it, generates stoppages when that person is missing, has high variability between operators, or has caused quality or safety incidents.

2. Capture expert knowledge

Sit down with the operator who best masters the process and documents each step. The important thing is to capture how he really does it, not how the machine manual says it should be done. The tricks, the adjustments, the signs that something is not right — that is the tacit knowledge that no manual contains.

3. Structure the SOP in sequential steps

Each SOP should have between 5 and 15 steps. If it has more, you are probably mixing several processes. Each step must be a concrete and verifiable action: "adjust the pressure to 2.5 bar", not "prepare the machine".

4. Add troubleshooting

For each step that could fail, document what to do if it goes wrong. This is what differentiates a useful SOP from a decorative document. The substitute operator not only needs to know what to do — he needs to know what to do when something doesn't go as expected.

5. Make it accessible where it is needed

A SOP that lives in a shared folder on the server is useless. The operator needs to access the instructions at the workplace, when you need them. If you have to go to a computer, find the folder, find the file and open it, you're not going to do it. Accessibility is what differentiates a SOP that is used from one that is ignored.

Common errors when implementing SOPs in SMEs

• Document everything at once: generates fatigue and abandonment. Start with 3-5 critical processes and expand later.
• Write SOPs from the office: if the operators who actually execute the process do not participate, the SOP will not reflect reality and no one will follow it.
• Create 40-page documents: a SOP must be able to be followed step by step in the workplace. If it looks like a university manual, no one is going to consult it.
• Do not update: an outdated SOP is worse than not having SOP, because it generates false confidence. You need a system that makes it easy to upgrade.
• Do not measure: if you don't know who consults what SOP, when and with what result, you cannot improve or demonstrate the ROI of documentation.

Software SOP: when it makes sense to use a tool

If you have 1-2 machines and 5 employees, a PDF document may be enough. But when the plant grows, the PDFs are lost, they become outdated, you don't know who consulted them and there is no way to guarantee that the operator follows the correct process.

A SOP software solves these problems: it centralizes the procedures, makes them accessible in the workplace, records who has consulted what, allows updating without reprinting, and generates data on the actual use of the SOPs.

This article is part of the series of practical guides on industrial operational documentation by GMV Solutions. If you want to know how much the lack of documented procedures in your plant is costing you, take our operational risk diagnosis — result in 2 minutes.