DSS-R.02.02 — Drywall Mud / Plaster Film

Drywall mud/plaster film is an appearance change on glass caused by gypsum-based joint compound or plaster particulates/binders deposited during taping, sanding, feathering, or cleanup. It presents as a chalky veil with drag wipes, finger/pad prints, and particulate halos, sometimes consolidated by moisture. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status.

• Powdery, matte veil with hand/cloth wipe arcs; heavier below joints/ceilings and at sill returns.
• Sanding plume footprints: broad fallout zones with feathered edges; drips/legs if water or wash-down occurred.
• Under raking: fine particulate pepper; may show tide lines where damp wipes dried.

Surface-catch class (MSRT)

• Typically SC-0 (loose/powder film on top of glass).
• SC-1 may appear when abrasive pads or dry wipe grinding created very shallow micro-texture during improper cleaning; SC-2 uncommon.
• Perform one light, non-marring pass on a small revealed test patch (substrate). Use polymer stylus if a functional coating is suspected. MSRT supports classification only.

Visual signature

• Uniform matte, chalky cast; wipe streaks with overlap edges; powder sheds to cloth.
• No chip-flank sparkle (not mechanical scoring unless later scrubbed with abrasive); no fused nodules/pits (not hot-particle).

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°-120°); use raking macros to resolve particulate and tide lines. Record distances/angles in-frame.=

Location / access

• Record pane ID and surface numbering (#1-#4; laminate-internal). If fallout is between panes (fixed parallax on #2/#3), classify CAT-5 by location (out of in-place scope) and refer.

Mechanism cue (context)

• Active drywall/plaster work, sanding, mixing stations, mud pans, sponge finishing, or power sanding nearby; protective film removed too early.

Assign CAT by visibility at acceptance geometry and MSRT after a controlled reveal test. Depth values are indicative-field measurement not required.

• CAT-1 (Benign / non-relief): Chalky veil/particulate only; SC-0 after true reveal; primarily angle/raking visible. Indicative relief: 0-10 μm (optical film).
• CAT-2 (Light): Persistent residue with tide-line halos or slight SC-1 from prior abrasive wiping; limited impact at standard view. Indicative relief: ~10-40 μm.
• CAT-3 (Moderate): Broad, high-contrast matte fields legible at standard distance where residue consolidated with moisture or was abraded into micro-texture (SC-1→SC-2 localized). Indicative relief: ~40-120 μm.
• Reclassify when: If underlying alkaline etch is evident (e.g., from cementitious wash, not gypsum) or linear scoring is present from abrasive pads → evaluate under Ch.02 (alkaline attack) or M.02 (mechanical abrasion) as applicable.
• CAT-5 (by condition/location): Between-pane/inaccessible by parallax, integrity indicators, or confirmed functional-coating loss on the surface to be worked → CAT-5.

CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not abrade to “force” removal during classification.

• vs. Paint overspray (R.02.01): Overspray shows coalesced micro-droplets and sometimes color tone; drywall/plaster is white, powdery, non-gloss, transfers to cloth.
• vs. Stucco/lime residue (R.02.03) / alkaline attack (Ch.02): Stucco/lime is coarser/grainier, can leave alkaline burn or etch; gypsum films are softer, generally non-etch unless improper abrasive cleaning was used.
• vs. Mineral staining/etch (Ch.03): Mineral veils follow water arcs/runs and can show ring halos; gypsum fallout maps to sanding plumes and wipe zones.
• vs. Silicone or sealant smears (R.01.xx): Those read oily/iridescent with tool-mark corduroy; gypsum films are matte/powder with wipe streaks.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; raking macros of powder texture, wipe overlaps, tide lines; context frames with active drywall/plaster areas. Record distance/angle in-frame.
• MSRT result (substrate): After a small reveal test patch, perform one light, non-marring pass; record SC-class (SC-0/SC-1/SC-2).
• Forms: Pane ID; product family & surface numbering; worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist; photos attached.
• Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e when the worked surface is a factory functional coating.

• R.02.02 Drywall Mud / Plaster Film - Chalky matte veil with wipe arcs/overlaps on surface #___; post-reveal test patch shows [SC-0/SC-1]; visible at [12/36/72 in] under VIS geometry. Morphology: powder particulate, tide lines, fallout plume; no chip-flank sparkle, no discrete pits. Classification: CAT-[1/2/3] by visibility and SC-class; CAT-5 if between-pane, integrity cues, or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.