DSS-E.01.03 — Soot / Particulate Pollution Film

Soot / particulate pollution film is an appearance change on glass produced by airborne particulates (carbon soot, diesel exhaust, industrial dust, ash) that accumulate as a dry, grey-black veil. It often shows directional deposition based on airflow, edge build, and finger “lift” windows where casual contact removed soil. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status.

• Neutral-to-cool grey haze to flat blackening in severe cases; matte look that dulls reflections.
• Hand/finger wipe arcs that print lighter; drip/rivulet darkening where water carried particulates.
• Heavier loading near roadways, loading docks, generators, chimneys, or parking structures; pronounced on horizontal ledges and frame heads.

Surface-catch class (MSRT)

• Typically SC-0 (dry particulate on top).
• SC-1 may appear where abraded while dusty (dirty microfiber, paper towels) created very shallow micro-texture; SC-2 suggests misclassification-check for M.02 abrasion fields or Th.01 hot-particle if pits/nodules present.
• 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

• Dry, soot-like film that transfers easily to a clean cloth; no oily gloss.
• In raking: fine, non-sparkling particulate; no chip-flank sparkle; no fused pits/nodules.
• Deposition bias: darker near upwind edges, exhaust/diesel paths, or stack influence.

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal and oblique sweep (~60°-120°); raking macros to show particulate texture and wipe windows. Record distances/angles in-frame.

Location / access

• Record pane ID and surface numbering (#1-#4; laminate-internal). Common on outboard (#1) faces; interiors (#4) affected in garages/mechanical rooms. Between-pane by parallax on #2/#3 → CAT-5 by location.

Mechanism cue (context)

• Traffic corridors, bus bays, diesel generators, industrial stacks, wildfire season, forklift aisles; dry black soil on frames/sills that transfers to cloth.

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

• CAT-1 (Benign / non-relief): Light soot veil; SC-0; mainly angle/raking visible; lifts completely on reveal patch. Indicative relief: 0-10 μm (optical film).
• CAT-2 (Light): Persistent dark veil with wipe windows; localized SC-1 from prior dusty wiping; limited standard-view impact. Indicative relief: ~10-40 μm.
• CAT-3 (Moderate): Wide-area darkening legible at standard distance (global contrast loss), with scattered SC-1; indicates long dwell/high deposition. Indicative relief: ~40-120 μm (film stack/compacted fines).
• Reclassify when: After true residue lift, modeled micro-texture or SC>0 persists → evaluate M.02 abrasion fields; if rust-toned dots/pits are evident, consider Th.01.02 grinder spark embed; if oily amber tone, see R.04.03 HVAC oil or R.04.04 kitchen grease.
• 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. HVAC aerosol/oil film (R.04.03): HVAC films feel oily, show wetting anomalies; soot is dry, transfers to cloth, with less wetting contrast.
• vs. Kitchen grease (R.04.04): Grease has amber tone, tacky feel, spatter; soot is grey/black, uniform, dry.
• vs. Nicotine/tar (R.04.05): Nicotine shows amber/brown cast and odor; soot is neutral/dark grey to black, odorless/combustion-like.
• vs. Mineral system (Ch.03): Minerals show white/grey rings/runs with crystalline edges; soot lacks crystalline borders and lifts dry.
• vs. Hot-particle peppering (Th.01.02): Hot-particle leaves pits/fused nodules and sometimes rust dots; soot is film-like with no pits.

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; raking macros of particulate texture, wipe windows, deposition gradients; façade context showing traffic/stack sources. 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.

• E.01.03 Soot / Particulate Pollution Film - Grey-black dry veil with wipe windows on surface #___; post-reveal test patch shows [SC-0/SC-1]; visible at [12/36/72 in] under VIS geometry. Morphology: dry transfer to cloth, deposition bias to source, no chip-flank sparkle, no pits. Classification: CAT-[1/2/3] by visibility and SC-class; reclassify to M.02 if abrasion remains post-lift, or to Th.01.02 if pits/nodules are present; CAT-5 if between-pane or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.