Ranges
Do not repeat units (even if expressed symbolically) around symbols such as an en-dash or a "times" symbols (e.g., 5–10in. or 5 x 10")
Spacing
Put a space on each side of em-dashes and "times" symbols: Under this rule — as illustrated by this sentence — spaces would separate dimensions of a measurement such as 2 x 4.
Unit Symbols and Abbreviations
Use straight quotes (") and straight apostrophes (') to express inches and feet symbolically.
Capitalize "V" for "volt."
If you are checking a symbol usage that is not in Lightolier's standard grammar guide (Guide to Grammar and Writing) email your question (or any answers that you might have found) to Justin Katz.
