STE uses normal English punctuation, but simply. Clear punctuation helps the reader see the structure of a sentence. STE also gives guidance on how to count words, because the sentence length limits depend on the word count.
Use simple punctuation
- Use full stops to end sentences. A full stop is often better than a comma and "and".
- Use commas to separate items and to separate a condition from the instruction: "If the light comes on, stop the motor."
- Use a colon to introduce a vertical list.
- Avoid semicolons in running text. Two short sentences are usually clearer.
- Use parentheses only for short additional information, for example a reference to a figure.
- Check the official specification for the exact punctuation rules.
Hyphens
- Hyphens can show which words go together, for example in some technical names and compound adjectives.
- Use hyphenated terms consistently. Do not write "cross-check" in one step and "cross check" in another.
How to count words
The STE sentence limits (20 and 25 words) use word counts. Typical counting principles:
- A number with its unit counts as one word, for example "25 N·m".
- A hyphenated word counts as one word.
- A technical name or a label written on the equipment counts as one word, for example the name of a switch.
- Check the official specification for the exact counting rules.
Lists instead of long punctuation
- If a sentence needs many commas, it probably contains a list. Use a vertical list.
- Start each list item in the same grammatical form.