SOP Maker › How to write an SOP

How to write a standard operating procedure

An SOP answers one question in writing: how does this job get done properly, by whoever is on shift today. Here are the seven steps, in the order that works.

Written from controlling procedures in a working food factory, where a procedure nobody follows turns up as a finding in the next audit.

1. Decide what the SOP is for and who has to follow it

Start by naming three things: the job, the people who do it, and the thing that goes wrong when it's done badly. "Cleaning the slicer" is a job. "Hygiene" is not. One job per document. If you find yourself writing "and then, if it's the dicer instead", you've got two SOPs and you should split them.

Be honest about who the reader is. If the job is done by an agency worker on their second night shift, the document has to work for that person, not for the technical manager who signs it. That single decision changes the vocabulary, the sentence length and how many photographs you need.

Scope also decides what kind of document you're writing at all. A short "do it this way" note for one machine is usually a work instruction sitting under an SOP, not an SOP in its own right. If you're unsure which you need, read SOP vs work instruction first.

In SOP Maker this is the Process name, Applies to and Sites fields at the top of the document.

2. Watch the job being done before you write anything

Almost every unusable procedure was written at a desk. Go and stand next to the person doing the work with a notebook, and write down what actually happens, in order, including the parts nobody mentions in a meeting: the valve that has to be cracked open first, the trolley that has to be moved before the guard will lift, the ten minutes of soak time everyone knows about and nobody wrote down.

Ask "why" at each step you don't understand. Sometimes the answer is a real control and belongs in the document in bold. Sometimes the answer is "because that's how Dave does it", and you've just found the thing your procedure needs to settle.

Then ask the operator to talk you through it a second time while you read your notes back. The gaps show up fast when someone who does the job hears your version of it.

Notes from the floor are what fills the Safe System of Work steps later.

3. Give the document a number, an owner and a date

A procedure without a unique number, a named owner, a revision number and a date isn't a controlled document. It's a leaflet. And you can't tell whether the copy laminated to the wall is the current one, which is the single most common reason a document-control check goes badly.

Pick the numbering scheme before you write your second document, not your twentieth. Something like SOP_HY_0004 – a prefix, a department code, a sequential number – is enough. What matters is that no two documents share a number and that the number never gets reused when a procedure is withdrawn.

Name a single owner. Not a department, a person. The owner is who gets asked when the line changes and the procedure needs updating.

SOP Maker issues the number per department and checks the whole folder for duplicates before it stamps one on.

4. Write the purpose and scope in plain words

Two short paragraphs at the top. Purpose: what this procedure is for, in one or two sentences a new starter would understand. Scope: where it applies, and just as importantly where it doesn't. Name the lines, the areas, the shifts, the products.

Say what's out of scope explicitly. "This procedure does not cover the CIP set, see SOP_HY_0011" saves an argument later and stops people using the wrong document for a job it was never written for.

Keep the language flat. No "shall", no "it is the responsibility of the operative to ensure that". Write "you" and "check" and "do not". People read instructions at 6am under bright lights, in a second language more often than not.

These are the Purpose & Scope and Key Points sections in the editor.

5. Break the job into steps someone new could follow

One action per numbered step, in the order it happens, each starting with a verb. "Isolate the machine at the wall switch." "Remove the blade guard." "Dilute the sanitiser to 1%." Not "the machine should be isolated and the guard removed prior to dilution of the chemical".

Put numbers wherever a number exists. Dilution rates, contact times, temperatures, torque settings, how many minutes the rinse runs. A step that says "clean thoroughly" cannot be followed or audited. A step that says "spray, leave for five minutes, rinse at 40 to 50 °C" can be both.

Add a photograph where words are slow. One picture of the correct guard position replaces a paragraph and removes the ambiguity completely. Take the photograph on the line, on the actual machine, not from the manufacturer's brochure.

Use Numbered steps, Steps + responsibility, or Step-by-step with photos, depending on which the job needs.

6. Add the hazards, the PPE and what to do when it goes wrong

List what can hurt the person or ruin the product. Be specific: "the blade stays sharp with the power off", "the caustic burns skin on contact", "wet floor for ten minutes after the rinse". Vague hazard lists get skimmed.

State the PPE required for this job, not the site-wide list. If the job needs cut-resistant gloves and a face shield and the rest of the site only needs a hairnet and a coat, that difference is the whole point of putting it on the document. Icons help here, because people recognise the shape faster than they read the caption.

Then write the part most procedures skip: what to do when it goes wrong. First aid for a splash, who to call, whether to stop the line, how to report it. Keep it on the same document as the method. Nobody goes and finds a second document while their forearm is stinging.

There are dedicated PPE tiles, Caution box and Emergency / first aid sections, and 158 icons to pull from.

7. Get it authorised, issue it, and set a review date

Someone other than the author reads it and signs it. That's what makes it authorised rather than just written. Ideally two people: the person who owns the process and the person who owns the standard. Their names go on the document, not in an email.

When it's signed, the status moves from Draft to Approved and the previous revision comes off the wall the same day. Two live versions of one procedure is worse than having none, because now two people are both certain they're right.

Put a review date in the header, and treat any change to the line, the chemical or the machine as an automatic trigger to review it early. Most procedures rot because the process changed and the paperwork didn't.

Status, Prepared by, Authorised by, revision number and Next review all live in the document-control header.

What makes an SOP fail

Four things, over and over:

• It was written by someone who has never done the job.
• It's too long to read in the time available, so people read the title and guess.
• Nobody can tell whether the copy on the wall is current.
• It describes the process that was supposed to happen rather than the one that does.

Every one of those is fixed at writing time, and none of them is fixed by better formatting.

See what a finished one looks like

The quickest way to judge the shape is to read a complete one. There's a full worked example here: a chemical safety and PPE procedure, with the document-control header, PPE icons, numbered steps, a caution box and a sign-off table.

If you want the section structures broken down before you start, the SOP templates page lists what each type of procedure usually contains.

Writing them in SOP Maker

SOP Maker is a free tool that builds the document while you write. It handles the numbering, the document-control header, the icons, and the printing, so the only thing left is the part only you can do: knowing how the job is actually done.

It runs in your browser and saves into a folder you pick on your own computer. Nothing is uploaded and there's no account.

Free, no sign-up. Authoring needs desktop Chrome or Edge.