Plainmark

A plainmark is a stencilled panel of the Orbital Habitats Compact's Compact Common Marking — the standard for marking infrastructure without script. One to four horizontal colour bands, read top to bottom, each pairing a fixed ground with a fixed figure class: black with ochre lozenges for hazard, slate-blue with bone-white chevrons for the way and its junction count, bone-white with black strokes and blocks for number, ochre with black rings for sealed breathable refuge. A diagonal bar across any band voids it. No letters, no numerals, no characters of any script: nothing to spell, and nothing to mistranslate.

Colour never carries meaning alone — each figure belongs to exactly one band, so a panel read under red emergency light loses nothing. Panels sit on the fixed frame beside a hatch, never on the moving leaf; the stack order is always hazard, way, count, refuge — bad news first; read down to the air.

The standard descends from generation-ark hull-stencilling and Belt depot custom, and it is scoped like the Compact standard it is: wall to wall in the five member habitats, dockside wherever mixed hulls berth in numbers, and nowhere it hasn't been carried. Polities letter their own corridors in their own scripts; species with other bodies and senses mark by their own conventions. It needs no translation only because it carries far less than language does — it can say what kind of thing, which way, how many, and whether the promise still holds, and nothing else: no names, no verbs, no tenses, no reasons.

Example: a crewer off a foreign hull, no word of any Compact language, follows ochre rings through smoke-darkened corridors to sealed air — reading shape where colour has gone, which is exactly the failure the grammar was built for. Full treatment: The Plainmark.