To write an SOP people follow, watch the task being done, write each step as one action in the order it happens, put warnings before the step they apply to, then test the draft with someone who did not write it. Approve it, train on it and review it on a fixed cycle.
Last reviewed: November 2026
A standard operating procedure (SOP) is a written, approved set of steps for doing a routine task the same way every time. It's followed when the people doing the work recognise their own job in it.
| Step | What you do | Why it matters |
|---|---|---|
| Scope | Name the task, where it starts and where it ends | Stops one SOP turning into a manual |
| Observe | Walk the task with the people who do it | Captures the real sequence, not the remembered one |
| Draft | One action per step, verb first, in order | Easy to scan at the workstation |
| Warn | Put cautions before the step they protect | People read warnings in time to act |
| Test | Have someone else run the draft | Exposes gaps the writer cannot see |
| Approve | Named owner signs and dates it | Makes the current version clear |
| Train and review | Teach it, then review on a set cycle | Keeps the SOP true to the work |
Why Do People Ignore SOPs?
People ignore SOPs when the document doesn't match how the work is really done, when it's too long to use at the point of work, or when nobody owns it. The UK Health and Safety Executive's guidance on procedures names inadequate procedures and over-reliance on them as common causes of failure, and says procedures don't replace competency.
An SOP should therefore be written as a reference for someone already trained. Where a step needs judgement, the SOP should say what to check and who to call.
How Do You Start Writing an SOP?
Start by fixing the scope in one sentence: the task, the trigger that starts it and the result that ends it. "Changing a filter on line 3 press, from machine stop to restart sign-off" is a scope. "Maintenance" is not.
Then go to where the work happens. HSE recommends walking and talking through the task with the people who will use the procedure. Note each action in order, the tools, the checks and the moments where people hesitate or improvise; those moments are where an SOP earns its place.
Before writing, decide who the reader is. The US Environmental Protection Agency's SOP guidance sets a useful bar: enough detail that someone with limited experience of the procedure, but a basic grounding, can carry it out unsupervised.
How Should SOP Steps Be Written?
SOP steps should be short, in the active voice and in the order the work happens. EPA's guidance asks for a concise, step-by-step, easy-to-read format and suggests a flow chart where the process branches. Four habits make the biggest difference:
- Start each step with a verb: "Close valve V-12", not "The valve V-12 should be closed".
- Keep one action per step. If a step contains "and then", split it.
- State the check that proves the step worked: "Confirm the gauge reads zero."
- Put every warning or caution directly before the step it protects, never at the end of the document.
Use names exactly as printed on the equipment or screen. For multilingual teams, write the master in plain English, then have a fluent supervisor confirm each translation.
Keep the document lean. Your SOP template holds the fixed sections; the steps themselves should fit on the screen or sheet at the workstation.
Who Should Write and Approve an SOP?
The person who performs the task should help write the SOP, and someone else should approve it. EPA's guidance recommends SOPs be written by subject-matter experts who do the work, reviewed by others with the right training and experience, and approved by management with a signature or electronic signature.
In practice that means three named roles on the document: a writer from the work area, a reviewer who knows the process and its risks, and an owner who approves it, dates it and keeps it current.
How Do You Test an SOP Before Release?
Test an SOP by having someone other than the writer carry it out exactly as written, while the writer watches and stays silent. EPA notes it's especially helpful when draft SOPs are tested by people other than the original writer.
Pick a newer operator, not the most senior one. Mark every step where they pause, ask or skip ahead, fix the wording and repeat with someone else. Test safety-critical tasks only under supervision with hazards controlled.
How Often Should an SOP Be Reviewed?
Review an SOP whenever the process, equipment or a related rule changes, and otherwise on a fixed cycle that your quality or safety system sets. EPA suggests a periodic review, for example every one to two years, with the review date recorded on the SOP. Some procedures have stricter rules: in the US, OSHA's lockout/tagout standard requires a periodic inspection of each energy control procedure at least annually. Indian sites should confirm the cycle their own regulators and certifications require with the safety officer.
A withdrawn SOP should be removed from the floor and archived, so only one approved version is ever in use.
When Should an SOP Become a Training Video?
An SOP is worth turning into a video when the task is visual, done by many people across shifts or languages, or when new joiners need to see it before they try it. The written SOP stays the controlled source; the video teaches it. Our guide on how to turn an SOP into a training video covers scripting and scene planning, and the AI training video accuracy checklist covers review.
Probbit makes safety and SOP training videos from approved procedures, with your supervisors reviewing each version. Delivery timing depends on approved source material, scope, languages and review rounds. If a procedure is ready, schedule a call and bring the signed SOP.