A guest has left a fingerprint on the glass of a framed drawing in the corridor. It is obvious, it is annoying, and there is a bottle of glass cleaner two metres away in your caddy. Reach for it and you will spray a solvent that wicks under the frame lip, runs into the mount and the paper, and stains a work on paper permanently. The correct action here is to do nothing and ask.
The One Rule
This is the entire cleaning permission that interior crew have:
Where the surface is sound and the piece is robust, you may lightly dust with a clean, soft brush or a dry, lint-free cloth. Nothing else. Ever.
That is it. No water. No damp cloth. No solvents, spirits or alcohol. No proprietary polish, wax or reviver. No silicone. No glass cleaner on a glazed work. No metal polish on silver or bronze. No compressed air, no vacuum against a surface, no sticky rollers, no spit, no bread, no cotton bud.
Before You Even Dust
Dusting is safe only when the surface is genuinely stable. Stop and ask if you see any of these:
- Flaking, lifting, cracking, cupping or powdery paint
- Loose gilding, gesso, veneer, inlay or gilt ornament
- Anything shedding, blooming, sticky or tacky to look at
- Contemporary or mixed-media work, unvarnished acrylic, or an unglazed pastel, charcoal or chalk drawing
- Any surface you cannot confidently identify
If in doubt, do nothing, tell the chief stew, and let the art adviser or a conservator decide.
The Never List
| Product or method | What it does |
|---|---|
| Glass cleaner on a glazed work | Wicks behind the glass and stains or destroys the paper |
| Any damp or wet cloth on a painting | Swells the canvas, softens varnish, lifts paint |
| Solvents, alcohol, white spirit | Dissolve varnish, paint, ink, patina and finish |
| Furniture polish, wax, reviver, oil | Builds a haze, traps dirt, alters an antique finish |
| Silicone-based sprays | Contaminate the surface permanently and defeat later conservation |
| Metal polish on bronze or antique silver | Strips patina and abrades the surface. Value gone |
| Vacuum, compressed air, feather duster | Snags, flexes, drives dust in, catches loose fragments |
Around the Work, Not On It
You can and should keep the environment immaculate. Dust the wall, the plinth base, the vitrine exterior, the floor and the shelf, working away from the work. Change your cloth. Do not lean, do not steady yourself on the frame, and never rest a bottle or a cloth on a plinth.
Onboard Notes
- The only tools are a soft brush and a dry lint-free cloth, used lightly, on sound surfaces.
- Fingerprints, marks, bloom, tarnish and grime are all a conservator problem, not a stew problem.
- Doing nothing is a professional decision and is always defensible. Improvising never is.
- This lesson gives no permission to treat, clean or restore any work of art.