error · Section 5: Procedural writing
Rule 5.1: Write short sentences with a maximum of 20 words
In procedural writing, including warnings, cautions, and other safety instructions, write short sentences with a maximum of 20 words each. If a sentence is longer than 20 words, split it into two or more shorter sentences rather than leaving it as one long sentence.
What a checker looks for
A clear deviation from the rule.
- Count the words in each sentence within procedural text (work steps, warnings, cautions, other safety instructions) and flag any sentence that exceeds 20 words.
- When a long sentence should be split, check whether the resulting actions occur at the same time or in immediate sequence (they belong together as sentences within one work step) versus at genuinely different times (they belong in separate numbered work steps), and flag an incorrect choice between the two.
What this rule does not cover
- Notes are governed by rule 5.5, not this rule — a note's sentences may be up to 25 words and are not flagged by the 20-word procedural limit.
How to fix it
Split a sentence over 20 words into two or more shorter sentences at a natural break (e.g. before "until" or "then"). Keep the resulting sentences together within the same work step if the actions are simultaneous or one is an immediate continuation of the other; otherwise place each in its own numbered work step.
Constraints on the fix
- Do not omit any instructional content when splitting a sentence.
- Do not create a new numbered work step for an action that must occur at the same time as the preceding action.
Examples
Not STE: Put preservation oil into the unit through the vent hole until the oil level is approximately 6 mm (0.24 inches) below the surface of the flange cover.
STE: Put preservation oil into the unit through the vent hole. Continue until the oil level is approximately 6 mm (0.24 in) below the surface of the flange cover.
Word limit
| Maximum words | Applies to | Excludes |
|---|---|---|
| 20 | procedural-work-step, warning, caution, safety-instruction | note |
Related rules
Where this fits in AI governance
A rule a checker can test is a rule a model can be held to. The same discipline, on the governance side of this site.
- Improper output handling
A procedural instruction acted on without a check is the same failure whether the reader is a technician or a downstream system. - Human-in-the-loop review
Procedures are where a generated instruction should not reach a reader without a person having read it first. - Output validation guardrails
A controlled language is a checkable output constraint. This is the control that treats model output as something to be checked rather than trusted.
Source
ASD-STE100 Issue 9, Section 5 - Procedural writing, page 1-5-1.
This page is commentary and does not reproduce the standard. About this rule pack.