DSS-Ch.02.03 — Efflorescence-Associated Surface Attack

Efflorescence-associated surface attack is alkaline exposure of glass from waterborne salts and pore solutions migrating out of concrete/masonry. As moisture evaporates, alkali-rich films and salt blooms at the glass interface can etch the exposed face, leaving grainy micro-texture and run/pool halos after residues are removed. Classification is appearance-only per VIS (method-agnostic). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status on Forms: Handle active efflorescence per site safety.

• Run-bloom halos beneath masonry/copings/headers where moisture exits; feathered white bloom contiguous with vertical run legs.
• Crust islands (thin, friable salt plates) at sill/gasket lines; after reveal, duller “shadow” remains with grainy micro-texture in raking light.
• Seasonality common (wet, cooling periods); may repeat at the same geometry after rain/dry cycles.

Surface-catch class (MSRT)

• SC-0 where salt residue only remains prior to reveal.
• SC-1 (slight) to SC-2 (clear) if etch formed beneath/within the bloom footprint. Perform one light, non-marring pass; polymer stylus if a coating is suspected. MSRT supports classification only.

Visual signature

• Feathered bloom edges and run halos; interiors read as milky/grainy frost after reveal.
• No chip-flank sparkle (not mechanical); no discrete fused nodules/pits (not hot-particle).

Viewing / lighting

• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°-120°) with raking light to resolve grain and bloom edges. Document distances/angles in-frame.

Location / access

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

Mechanism cue (context)

• Masonry/concrete interfaces above the lite; weep paths; sealant discontinuities; recurrent moisture events; visible white salt bloom on adjacent porous materials.

Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth ranges are indicative-measurement not required.

• CAT-1 (Benign / non-relief): Bloom/film only, clears at reveal; SC-0; visible mainly in raking. Indicative relief: 0-10 μm.
• CAT-2 (Light): Subtle etched halos/fields with SC-1; grain evident in raking; limited impact at standard view. Indicative relief: 10-40 μm.
• CAT-3 (Moderate): SC-2 across broader run-bloom regions; grainy frost legible at standard distance; persistent halo geometry. Indicative relief: 40-120 μm.
• CAT-4 (Severe): Pronounced matte/frosted swaths with repeated cycles; distinct at standard & wide-field; may show opaque edge crust shadows. Indicative relief: 120-300 μm+.
• CAT-5 (by condition/location): Between-pane/inaccessible by parallax, integrity indicators (active cracks, pane movement), 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 “probe” with MSRT.

• vs. Concrete splash/run-off (Ch.02.02): Concrete splash yields speckled constellations/curtain bands tied to one-time events; efflorescence attack shows recurrent bloom halos following moisture/weep paths.
• vs. HCl brick-wash fallout (Ch.01.02): HCl runs have cleaner frost with sharper borders; efflorescence often leaves feathered white bloom and granular ghosting after reveal.
• vs. Organic-acid footprints (Ch.01.03): Biogenic patches are localized ovals with pool centers; efflorescence tracks porous-substrate moisture patterns (joints/headers/weep).
• vs. Residue films (R-family): Detergent/soot films remove at reveal and remain SC-0; etched bloom persists with SC-class > 0.
• vs. Coating anomalies (Co-family): Coating rub/patchiness shows sheen/color change but no etched relief; on a worked coated surface any anomaly is not permitted at acceptance (VIS §6.2.e).

• Photo set (VIS): 12 / 36 / 72 in, normal + oblique; include raking macros resolving bloom edges/grain; add context frames showing weep paths, joints, porous substrates. Record distance/angle in-frame.
• MSRT result: One light, non-marring pass on representative halo/interior; record SC-class (SC-0/1/2). Prefer polymer stylus if a coating is suspected.
• 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.

• Ch.02.03 Efflorescence-Associated Surface Attack - Run-bloom halos / crust islands with [SC-1/SC-2] on surface #___, visible at [12/36/72 in] under VIS geometry after Non-Invasive Reveal. Morphology: feathered bloom edges with grainy micro-texture; no chip-flank sparkle or discrete pepper. Classification: CAT-[2/3/4] by relief/visibility; CAT-5 if between-pane, integrity cues, or coating-side loss on the surface to be worked. Forms + photo set completed; acceptance per VIS-A §6 (separate).