Reviewed 18 August 2026 · next review 17 February 2027
A technical writing style guide you can apply this afternoon
Style guides fail when they are long and abstract. These twelve rules are short, each one shows the failing sentence and the fix, and every one of them is machine-checkable.
Last updated · Written and reviewed by Jonatan Tensetti · Tensetti Tools
Method 1.0.0 · reviewed 18 August 2026 · next review 17 February 2027
The rules below are the human-readable version of what the checker looks for. There are 22 checks in total; these twelve carry most of the improvement in everyday procedures. Adopt them as your house style and the score follows on its own.
- 01
One action per step
Before
Remove the cover and disconnect the battery, then check the fuse.
After
1. Remove the cover. 2. Disconnect the battery. 3. Check the fuse.
Steps are also a checklist. Three actions on one line means two of them get skipped under pressure.
- 02
Name the actor
Before
The valve should be closed before servicing.
After
Close the valve before you service the pump.
Actorless sentences leave the reader guessing whether the machine, the software or they themselves must act.
- 03
Front the condition
Before
Press Start after the indicator turns green and the guard is locked.
After
When the indicator is green and the guard is locked, press Start.
A reader who acts on the first clause has already acted before reaching the condition.
- 04
One term per concept
Before
the housing / the enclosure / the case
After
the housing
Three names for one part turns search into guesswork and translation into invention.
- 05
Say what 'it' is
Before
Attach the bracket to the frame and tighten it.
After
Attach the bracket to the frame, then tighten the bracket bolts.
Ambiguous pronouns are the cheapest mistake to make and the most expensive to support.
- 06
Give an observable result
Before
Configure the interface appropriately.
After
Set the interface to 100 Mbit/s. The link LED turns solid green.
A step without a result cannot be verified, so nobody knows whether it worked.
- 07
Replace vague quantifiers
Before
Tighten the bolts sufficiently.
After
Tighten the bolts to 12 Nm.
"Sufficient", "appropriate" and "as required" transfer your decision to someone with less information.
- 08
Keep sentences short
Before
A 41-word sentence with three subordinate clauses.
After
Two sentences of about fifteen words each.
Long sentences in instructions cause re-reading, and re-reading in a workshop causes errors.
- 09
Prefer positive instructions
Before
Do not fail to disconnect the supply before opening the panel.
After
Disconnect the supply before you open the panel.
Double negatives invert meaning under stress and translate badly.
- 10
Warnings in a fixed order
Before
Be careful with the heater.
After
WARNING: Hot surface. Contact causes burns. Let the heater cool for 30 minutes before you touch it.
Signal word, hazard, consequence, avoidance. Readers scan for the avoidance line; give them one.
- 11
Cut filler openings
Before
It should be noted that the device requires calibration.
After
Calibrate the device.
Filler pushes the instruction to the end of the sentence, where scanning readers miss it.
- 12
Expand an abbreviation once
Before
Set the PDU to standby via the BMC.
After
Set the power distribution unit (PDU) to standby using the baseboard management controller (BMC).
Your reader is not always the person who wrote the specification.
How to roll this out without a committee
- Pick one document that people complain about.
- Run it through the checker and read the first ten findings.
- Fix only the actor, ambiguity and safety findings on the first pass.
- Agree the term list that came out of it — that is your termbase.
- Apply the same twelve rules to the next document you write, not retrospectively to all of them.
A finding is a prompt to look, not a verdict. Judgement stays with the author: some passive sentences are correct, and some long sentences are the clearest option available.
ClearSpec uses an independent proprietary clarity method. It is not affiliated with ASD/STEMG, is not an ASD-STE100 checker or certification service, and does not certify ISO 24495-1 conformance.
References
Checked 18 August 2026. Referenced for context only; no standard text or dictionary content is reproduced.
- ISO 24495-1:2023 Plain language — Part 1 — ISO. Official standard information page. Context only; the standard is not reproduced or certified.
- Official ASD-STE100 site — ASD Simplified Technical English Maintenance Group. Ownership, current resources and trademark context. ClearSpec is not affiliated with ASD/STEMG.
- ASD-STE100 official downloads and AI white paper — ASD STEMG. Official materials. Copyright and stated limitations respected; no dictionary content is copied.
- Clear content objective — W3C WAI. Accessibility-oriented clear-content guidance informing general principles.
- Writing for web accessibility — W3C WAI. First-party accessibility writing tips informing general principles.
22 checks, no account, and the text is analysed in your browser.
ClearSpec reports automated heuristics from method version 1.0.0. The clarity indicator is not a measure of technical accuracy, usability, legal sufficiency, safety or standards conformance. A competent person must decide the final wording, especially for safety content.
Frequently asked questions
- What makes a procedure step clear?
- One action per step, a named actor, and an observable result. If a reader cannot tell who acts or how they know the step succeeded, the step is not finished.
- Is passive voice always wrong in technical writing?
- No. Passive is a problem when it hides the actor in an instruction. It is often the right choice when the actor is irrelevant or unknown, such as in descriptions of system behaviour.
- How many terms should a termbase start with?
- Start with the terms that already have two or three competing names in your documents. Twenty entries that resolve real ambiguity beat a two-hundred-entry glossary nobody maintains.
- Does the checker rewrite my text?
- No. It flags sentences deterministically against 22 named checks and leaves the edit to you. Nothing you paste leaves your browser.