ClearSpec

Reviewed 18 August 2026 · next review 17 February 2027

Simplified Technical English: what an independent checker can and cannot tell you

Read this before you buy any tool that promises Simplified Technical English compliance.

Last updated · Written and reviewed by Jonatan Tensetti · Tensetti Tools

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.

What Simplified Technical English is

ASD-STE100, usually called Simplified Technical English, is a controlled-language specification developed and maintained by the ASD Simplified Technical English Maintenance Group. It combines writing rules with a controlled dictionary of approved words and approved meanings, and it originated in aerospace maintenance documentation. The specification and its dictionary are the property of ASD; obtain them from the official source rather than from a third-party summary.

What an independent checker can genuinely do

A deterministic tool can measure structural properties of your text without knowing anything about a proprietary dictionary: sentence length, several actions inside one step, passive constructions with no actor, unmeasurable words, stacked nouns, nested conditions, inconsistent term forms, inconsistent units and incomplete warning structure. Those are the 22 checks ClearSpec runs.

If the pressure is high and if the alarm is active, the valve is closed and the pump is stopped.
  • CS_NESTED_CONDITION — The sentence contains 2 conditional markers. Split the branches into separate sentences or a decision list.
  • CS_PASSIVE_ACTION — The action is written in the passive voice and no actor is named. Name the actor and use an active instruction, for example 'The technician closes the valve.'

Possible false positive: A short two-branch condition can be clear enough in a specification.

What it cannot do

  • It cannot tell you that a word is approved or unapproved in the STE dictionary.
  • It cannot certify conformance with ASD-STE100 or with ISO 24495-1.
  • It cannot judge technical accuracy, legal sufficiency or safety.
  • It cannot replace a qualified reviewer or a controlled-language deployment programme.

How to choose honestly

If your contract requires ASD-STE100, start with the official specification and the official resources, and treat any tool — including this one — as an aid inside your own process. If what you actually need is consistent, unambiguous instructions, a transparent structural checker gives you measurable improvements without a compliance claim nobody can back.

Run the independent clarity checks

22 checks, no account, and the text is analysed in your browser.

Questions

Is ClearSpec an ASD-STE100 checker?
No. ClearSpec is an independent clarity checker with its own rule set. It is not affiliated with ASD or STEMG and does not implement, reproduce or certify the ASD-STE100 specification or its dictionary.
Can any tool certify STE compliance?
Software can support writers, but the specification is owned and maintained by ASD STEMG and compliance decisions belong to the organisations and people applying it, not to an automated indicator.
What does ClearSpec check instead?
22 named rules for action clarity, sentence structure, terminology consistency, safety-language structure and formatting consistency, each with the exact span, a reason and one editing action.

References

Checked 18 August 2026. Referenced for context only; no standard text or dictionary content is reproduced.

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.