Welding slag spatter presents as fused metallic nodules and/or resultant pits/craters formed when hot particles (weld spatter) impact and partially fuse to the glass, often followed by detachment leaving a pitted field. Classification is appearance-only per VIS; methodology is out of scope. Inspect under VIS lighting/geometry after Non-Invasive Reveal; record surface numbering and worked-surface status on Forms: Use the Manual Surface-Relief Test (MSRT) only as a single, non-marring pass to confirm relief; it does not determine acceptance.

• Peppered field of dark or metallic specks; some remain proud/fused, others have detached, leaving bright, crater-like pits with halo in raking light.
• Often clustered on elevations adjacent to welding operations (balustrades, canopy frames, stair rails).
• May coexist with grinding sparks (ferrous “pepper”) and heat tinting on nearby metals.

• Surface-catch class (MSRT)
• On fused nodules, a light, single pass typically yields SC-2 (clear); on detached pits, SC-1 to SC-2. Do not abrade; one non-marring pass only; polymer stylus if a coating is suspected.
• Visual signature
• Discrete, high-contrast nodules (sometimes metallic sheen) and sharp-edged micro-craters; bright chip-flank sparkle at pit edges under raking.
• Fields may show directional bias toward the source; individual pits do not track as continuous lines (distinguishes from linear scoring).
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°–120°) using raking light to reveal relief.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If parallax or construction indicates a between-pane condition, classify CAT-5 by location (out of in-place scope).
• Mechanism cue (context)
• Welding slag / grinder overspray is a typical origin for severe mechanical-thermal fields. (Informative linkage from VIS category notes.)

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Numeric depth bands are indicative only—measurement is not required for classification.
• CAT-2 (Light): Sparse nodules/pits; SC-1 (slight) to SC-2 (clear) on a few features; visible mainly in raking at close/standard view. Indicative depth: ~20–60 μm (pit diameter typically ≤0.3 mm).
• CAT-3 (Moderate): Clustered field, numerous clear-catch pits with bright flanks; noticeable at standard distance. Indicative depth: ~60–150 μm; mixed nodules and detached pits.
• CAT-4 (Severe): Dense peppering / crater field, frequent fused nodules with rough micro-flanks, occasional micro-fracture lips at pit margins; visible at standard & wide-field. Indicative depth: ~150–400 μm+.
• CAT-5 (by location/condition): Between-pane cues, active cracks, pane movement, or coating-side loss on the surface to be worked → CAT-5 (non-repairable/out of in-place scope).
• CAT is appearance-based; acceptance is separate and governed by VIS §6 at 12/36/72 in under defined conditions.

• vs. Grinder spark embed (Th.01.02): Grinder pepper tends to be finer, more uniform; welding slag shows larger, irregular nodules/pits with higher local energy signatures.
• vs. Sand abrasion (E.02.01): Eolian matte is broad, directional micro-texture (field haze) rather than discrete fused droplets.
• vs. Coating anomalies (Co.01/Co.03): Coating rub/patchiness lacks fracture facets/pits and shows sheen/color shifts rather than fused bodies; also governed by coated-surface acceptance rules on the worked surface.
• vs. Linear scoring (M.01): Scores form continuous tracks; slag presents as discrete peppering without long run-length.

1. Photo set (VIS): 12 / 36 / 72 in; normal + oblique; include raking macros resolving facet/halo at representative pits and at least one context frame showing proximity to weld source. Record distance/angle in-frame.
2. MSRT result: One light, non-marring pass on a representative nodule/pit; SC-class = SC-1/SC-2 as observed; polymer stylus where a coating is suspected.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS §6 at 12/36/72 in; classification ≠ acceptance. Coating anomalies on a worked coated surface remain disallowed at acceptance per VIS §6.2.e.

Th.01.01 Welding Slag Spatter — Discrete fused nodules / pits on surface #___ documented at 12/36/72 in, normal + oblique with raking; MSRT = SC-[1/2] on representative features. Morphology shows peppered field with crater halos; no continuous linear scoring observed. Classification: CAT-[2/3/4] by density and relief; CAT-5 if between-pane, active cracks, or coating-side loss on the surface to be worked. Forms + photo set completed; acceptance per VIS §6 (separate).

Grinder spark embed presents as a fine “peppered” field of ferrous particles ejected from metal grinding/cutting that impact, fuse, and/or oxidize on the glass. Some particles remain proud/fused; others detach leaving micro-pits. Classification is appearance-only per VIS; methodology is out of scope. Inspect under VIS lighting/geometry after Non-Invasive Reveal; record surface numbering and worked-surface status on Forms:

• Broad fine peppering oriented toward the grinding work area; individual particles appear dark/rust-colored specks; where detached, bright micro-craters show in raking light.
• Often more uniform and finer than welding slag spatter; can extend across panels aligned with airflow or gravity.
• May include light rust halos around retained ferrous specks.

• Surface-catch class (MSRT)
• On retained specks and micro-pits, a single, light, non-marring pass typically yields SC-1 (slight) to SC-2 (clear) on representative features. Do not abrade; one pass only. Use a polymer stylus if a coating is suspected. MSRT supports classification only.
• Visual signature
• High-density field of minute, discrete points; many with tiny bright pit rims in raking light; lacks long continuous tracks of linear scoring.
• Some specks show oxidized (brown) tonality; pits read as sparkly rims under oblique.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°–120°) with raking light per VIS.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If fixed parallax indicates between-pane, record CAT-5 by location (out of in-place scope).
• Mechanism cue (context)
• Frequently associated with construction grinding/cutting near exposed glass (rebar, studs, railings), producing nearly molten shards that embed in the surface.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth bands below are indicative only—numeric measurement not required for field classification.
• CAT-2 (Light): Sparse to light peppering, mostly SC-1 on select points; visible mainly at raking and close/standard view; limited field impact. Indicative pit depth: ~10–40 μm; pit diameter commonly ≤0.2 mm.
• CAT-3 (Moderate): Noticeable cluster fields with frequent SC-2 micro-pits and bright rims; clearly visible at standard distance; occasional retained specks. Indicative pit depth: ~40–120 μm.
• CAT-4 (Severe): Dense, widespread peppering; many clear-catch pits and intermittent fused nodules; readily apparent at standard and wide-field views. Indicative pit depth: ~120–300 μm+.
• CAT-5 (by location/condition): Between-pane cues, active cracks/pane instability, or confirmed functional-coating loss on the surface to be worked → CAT-5 (non-repairable/out of in-place scope).
• CAT is appearance-based; acceptance is separate and governed by VIS §6 at 12/36/72 in under defined conditions.

• vs. Welding slag spatter (Th.01.01): Slag fields tend to include larger fused nodules and rougher craters; grinder pepper is finer, more uniform and more “dust-like.”
• vs. Linear scoring (M.01): Scoring forms continuous lines with abrasive chip-flank sparkle; peppering is discrete points without run-length.
• vs. Sand abrasion (E.02.01): Eolian abrasion appears as directional matte fields (non-discrete) and may show modeled micro-texture rather than discrete pits.
• vs. Coating anomalies (Co.01/Co.03): Coating rub/patchiness shows sheen/color shift without pit rims; coating anomalies on the worked coated surface are not permitted at acceptance.

1. Photo set (VIS): 12 / 36 / 72 in; normal + oblique; include raking macros that resolve pit rims/retained specks and at least one context frame showing proximity to grinding operations. Record distance/angle in-frame.
2. MSRT result: One light, non-marring pass on a representative spot; record SC class (SC-1/SC-2 as observed). Prefer polymer stylus if a coating is suspected.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS §6 at 12/36/72 in; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e.

Th.01.02 Grinder Spark Embed (Ferrous Peppering) — Fine discrete pepper field with retained specks / micro-pits on surface #___ documented at 12/36/72 in, normal + oblique with raking; MSRT = SC-[1/2] on representative points. Morphology shows discrete pits with bright rims; no continuous scoring. Classification: CAT-[2/3/4] by density and relief; CAT-5 if between-pane, integrity cues, or coating-side loss on the surface to be worked. Forms + photo set completed; acceptance per VIS §6 (separate).

Oxy-fuel/plasma specking presents as fine to mixed-size hot-particle spatter from flame-cutting or plasma-cutting operations that impact and partially fuse to the glass, often oxidizing (dark/brown/blue tones) and/or detaching to leave micro-craters. Classification is appearance-only per VIS (method-agnostic). Inspect under VIS lighting/geometry after Non-Invasive Reveal; record surface numbering and worked-surface status on Forms: Use the Manual Surface-Relief Test (MSRT) only as a single, non-marring pass to confirm relief; it does not determine acceptance.

• Discrete speck field downrange of oxy-fuel/plasma work (balconies, rail steel, façade steel).
• Mix of very fine points and occasional larger blisters/nodules; many show oxidation colors (brown to straw/blue) on retained particles.
• Where particles have popped off, bright-rimmed micro-craters remain; raking light reveals sparkly flanks.

• Surface-catch class (MSRT)
• Retained specks and micro-craters typically read SC-1 (slight) to SC-2 (clear) on a single, light, non-marring pass. Do not abrade; use a polymer stylus if a coating is suspected. MSRT supports classification, not acceptance.
• Visual signature
• Discrete, non-linear peppering with oxidized color notes on retained particles; micro-craters with bright, rough rims where detachments occurred.
• Usually finer and more uniform than welding slag, but coarser/less uniform than grinder pepper depending on process and standoff.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°–120°) using raking light to resolve rims/oxidation.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If fixed parallax indicates a between-pane presentation, classify CAT-5 by location (out of in-place scope) and refer.
• Mechanism cue (context)
• Often aligned with cut direction and gravity/airflow from oxy-fuel/plasma operations; may co-occur with heat tint on nearby metal substrates.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Numeric depth ranges are indicative—measurement is not required for classification.
• CAT-2 (Light): Sparse/light peppering; mostly SC-1; visible primarily in raking at close/standard view. Indicative pit depth: ~20–60 µm; typical pit dia. ≤~0.3 mm.
• CAT-3 (Moderate): Noticeable clusters/fields with frequent SC-2 micro-craters and occasional retained, oxidized specks; clearly visible at standard distance. Indicative pit depth: ~60–150 µm.
• CAT-4 (Severe): Dense peppering, numerous clear-catch craters and intermittent fused nodules; readily apparent at standard & wide-field views. Indicative pit depth: ~150–400 µm+.
• CAT-5 (by location/condition): Between-pane/inaccessible by parallax, active cracks/pane instability, or confirmed functional-coating loss on the surface to be worked → CAT-5 (non-repairable/out of in-place scope).
• CAT is appearance-based; acceptance is separate and governed by VIS §6 at 12/36/72 in under defined conditions.

• vs. Welding slag spatter (Th.01.01): Slag often shows larger, irregular fused nodules; oxy-fuel/plasma specking trends finer with oxidation colors more evident on retained particles.
• vs. Grinder pepper (Th.01.02): Grinder fields are typically very fine and uniform, with fewer color tones; oxy-fuel/plasma can show a wider particle size spread and oxidized hues.
• vs. Linear scoring (M.01): Scores are continuous lines; specking is discrete points without run-length.
• vs. Coating anomalies (Co-family): Coating rub/patchiness shows sheen/color shifts without pit rims/fused bodies; on a worked coated surface, any anomaly is not permitted at acceptance (VIS §6.2.e).

1. Photo set (VIS): 12 / 36 / 72 in; normal + oblique; include raking macros that resolve pit rims/retained specks and at least one context frame showing proximity to the cutting operation. Record distance/angle in-frame.
2. MSRT result: One light, non-marring pass on a representative spot; record SC class (SC-1/SC-2 as observed). Prefer polymer stylus if a coating is suspected.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS §6 at 12/36/72 in; classification ≠ acceptance. Coated-face appearance rules apply per VIS §6.2.e.

Th.01.03 Oxy-Fuel / Plasma Specking — Discrete hot-particle speck field with oxidized retained specks / bright-rimmed micro-craters on surface #___, documented at 12/36/72 in, normal + oblique with raking; MSRT = SC-[1/2] on representative points. Classification: CAT-[2/3/4] by density and relief; CAT-5 if between-pane, integrity cues, or coating-side loss on the surface to be worked. Forms + photo set completed; acceptance per VIS §6 (separate).

Torch proximity streaking is a localized, elongated appearance change on the exposed face caused by nearby torch/heat tool use (e.g., soldering, brazing, roofing/flashing work). It presents as a streak or band of tone/shine shift and may include modeled micro-texture when the surface has been thermally softened. 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:

• Linear/curvilinear band aligned with torch travel or radiant plume, often tapering with distance from the source.
• Sheen/contrast change in specular view; in raking light may show very fine modeled micro-texture (non-directional).
• May co-occur with soot film (removable) adjacent to a smaller core streak that remains after reveal.

• Surface-catch class (MSRT)
• SC-0 when the effect is purely optical/thermal tint or subtle gloss shift (no relief).
• SC-1 (slight) when very shallow micro-texture is present; SC-2 (clear) is uncommon but possible where softening produced minute relief. Perform one light, non-marring pass; polymer stylus if a coating is suspected. MSRT supports classification only.
• Visual signature
• Continuous band with soft boundaries (no worked “ring”); no chip flanks, pits, or crater pepper.
• Non-linear grain under raking (if present) reads modeled, not directional scratch webbing.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°–120°) with raking light to resolve any micro-texture. Document distances/angles in-frame.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If parallax shows a between-pane look-alike, classify CAT-5 by location and refer per project protocol.
• Mechanism cue (context)
• Proximity to roofing torches, HVAC brazing, flashing work, or open flame; look for directional soot trails and heat-affected metals nearby.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth bands below are indicative—numeric measurement not required.
• CAT-1 (Benign / non-relief): Sheen/tone shift only, SC-0, no modeled texture; visible mainly in raking at close/standard view. Indicative relief: ~0–10 µm (optical only).
• CAT-2 (Light): Subtle modeled micro-texture, SC-1 (slight); limited impact at standard view; no chip flanks. Indicative relief: ~10–40 µm.
• CAT-3 (Moderate): Clear detect (SC-2) with visible modeled micro-texture at standard view; boundaries remain soft (no transition ring). Indicative relief: ~40–120 µm.
• CAT-4 (Severe): Pronounced matte/frosted band due to thermal softening/devitrification; distinct at standard & wide-field views; still no pits/craters. Indicative relief: ~120–300 µm+.
• CAT-5 (by location/condition): Between-pane/inaccessible by parallax, integrity indicators (active cracks, pane movement), or confirmed coating-side 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 use MSRT to “probe” or alter surfaces.

• vs. Oxy-fuel/plasma/grinder pepper (Th.01.xx): Hot-particle damage shows discrete nodules/pits with bright rims; torch streaking is a continuous band without discrete pepper.
• vs. Linear scoring (M.01): Scoring forms continuous abrasive lines with chip-flank sparkle; torch streaks show modeled (non-directional) micro-texture or sheen shift.
• vs. Residue films (R-family): Soot and condensate remove at reveal (SC-0). Persisting core band suggests thermal effect → classify here.
• vs. Coating anomalies (Co-family): Coating rub/patchiness may present sheen/color shifts but is governed by coated-surface acceptance; any anomaly on the worked coated face is not permitted at acceptance.
• vs. Roller wave / bow (P.01): Factory flatness features are pane-scale, periodic or global and SC-0; torch streaking is local and may show SC-1/SC-2.

1. Photo set (VIS): 12 / 36 / 72 in, normal + oblique, include raking macros resolving any micro-texture; add context frames showing suspected heat source alignment. Record distance/angle in-frame.
2. MSRT result: Record SC-class (SC-0/1/2) with one light, non-marring pass (polymer stylus if a coating is suspected).
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coating-side anomalies on the worked surface remain disqualifying.

Th.02.01 Torch Proximity Streaking — Localized heat-affected band on surface #___ with [SC-0/SC-1/SC-2]; no pits/craters or chip flanks; visible at [12/36/72 in] under VIS geometry after Non-Invasive Reveal. Morphology: sheen/contrast shift ± modeled micro-texture; boundaries soft (no worked ring). Classification: CAT-[1/2/3/4] by cues; CAT-5 if between-pane/integrity or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.

An overheated grinder/belt burn line is a localized, elongated band produced when a powered abrasive (grinder, belt, pad, or wheel) is run against the glass (often inadvertently) long enough to generate frictional heat. The result is a tone/shine shift (and, at higher severities, modeled micro-texture/matte) along the tool path. 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:

• Linear/curvilinear band tracking tool travel, sometimes with a feathered head/tail and central hot core.
• In specular view: duller gloss or color/contrast shift vs. adjacent glass; in raking light: non-directional, modeled micro-texture within the band.
• May show light residue (rubber/compound) that clears at reveal, leaving the core burn band visible.

• Surface-catch class (MSRT)
• SC-0 when effect is optical only (gloss/tone shift without relief).
• SC-1 (slight) where very shallow micro-texture is present; SC-2 (clear) is uncommon but possible on severe overheats approaching frosted appearance. Perform one light, non-marring pass (polymer stylus if a coating is suspected). MSRT supports classification only.
• Visual signature
• Continuous band with soft boundaries; no discrete pits/craters and no chip-flank sparkle typical of scoring.
• Texture inside the band reads modeled (non-directional), not a swirl/web of abrasive scratches.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence and oblique sweep (~60°–120°) with raking light to resolve any micro-texture; document distances/angles in-frame.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If parallax demonstrates a between-pane look-alike, classify CAT-5 by location and refer per project protocol.
• Mechanism cue (context)
• Nearby evidence of powered abrasives (handheld grinders, belts, polishers), belt tracking marks on adjacent finishes, or compound/rubber smear at band edges.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth/relief values are indicative—no measurement required.
• CAT-1 (Benign/non-relief): Sheen/tone shift only; SC-0; visible primarily in raking at close/standard view. Indicative relief: ~0–10 µm (optical only).
• CAT-2 (Light): Subtle modeled micro-texture, SC-1; limited impact at standard view; boundaries remain soft. Indicative relief: ~10–40 µm.
• CAT-3 (Moderate): Clear detect (SC-2) with apparent modeled micro-texture at standard view; still no pits/craters, no chip flanks. Indicative relief: ~40–120 µm.
• CAT-4 (Severe): Pronounced matte/frosted lane from overheating/incipient devitrification; distinct at standard & wide-field views; no discrete pepper. Indicative relief: ~120–300 µm+.
• CAT-5 (by location/condition): Between-pane/inaccessible by parallax, integrity indicators (active cracks/pane movement), or confirmed coating-side 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 use MSRT to “probe” or alter surfaces.

• vs. Linear scoring (M.01): Scoring shows abrasive lines with chip-flank sparkle and SC-2 along edges; burn lines show modeled micro-texture/gloss shift with soft boundaries.
• vs. Torch proximity streak (Th.02.01): Torch bands align with a heat plume and may accompany soot films; belt/grinder burns track tool contact and often coincide with rubber/compound smears (removable).
• vs. Hot-particle peppering (Th.01.xx): Slag/sparks present discrete fused nodules or pits with bright rims; burn lines lack discrete pepper.
• vs. Residue films (R-family): Films clear at reveal and read SC-0; a persisting core band with SC-1/2 micro-texture indicates thermal burn.
• vs. Coating anomalies (Co-family): Coating rub/patchiness shows sheen/color change but — if on a worked coated surface — is not permitted at acceptance; confirm coating presence and apply VIS §6.2.e.

1. Photo set (VIS): 12 / 36 / 72 in, normal + oblique, include raking macros resolving micro-texture within the band; add context frames showing tool path or nearby abrasive equipment. Record distance/angle in-frame.
2. MSRT result: Record SC-class (SC-0/1/2) with one light, non-marring pass; polymer stylus on suspected coated faces.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coating-side anomalies on the worked surface remain disqualifying.

Th.02.02 Overheated Grinder/Belt Burn Line — Localized heat-affected band on surface #___ with [SC-0/SC-1/SC-2], no pits/craters or chip flanks; visible at [12/36/72 in] under VIS geometry after Non-Invasive Reveal. Morphology: sheen/contrast shift ± modeled micro-texture; boundaries soft. Classification: CAT-[1/2/3/4] by cues; CAT-5 if between-pane/integrity or coating-side loss on the surface to be worked. Forms + photo set attached; acceptance per VIS-A §6.

A differential heating stress crack is a through-thickness (or actively propagating) fissure that initiates when nonuniform heating/cooling creates thermal stress exceeding glass strength, commonly at edges/corners or hardware penetrations. Any confirmed crack is an integrity condition and is out of in-place restoration scope (CAT-5 by condition/location). This DSS defines identification and documentation; it does not prescribe repair. Inspect under VIS lighting/geometry after a Non-Invasive Reveal; record surface numbering and worked-surface status on Forms:

• Filament-thin, continuous line emanating from an edge, corner, hole, or notch root, extending inward; may show kinks/branching where stress redistributes.
• Often associated with local heat sources (space heaters, IR lamps, roofing torches, sun/reflector hot-spots, heated film edges) or shadow lines (curtains/blinds, frit/opaque zones).
• Can appear suddenly after a thermal event; may be accompanied by a soft “tick” sound and immediate growth.

• Surface-catch (MSRT).
• Do not pass a stylus across any suspected crack. If needed, a single light, non-marring pass adjacent to the origin chip/edge may document local relief context only. MSRT is auxiliary and never determinative for integrity.
• Visual signature
• Phase-stable, continuous filament that persists through small viewpoint shifts; unlike scratches, it can traverse faint films/texture without loss of continuity.
• Origin evidence: edge chip/flare, corner stress focus, hole/notch root, or hot-spot locus (e.g., behind a heater).
• No abrasive chip-flank sparkle typical of scoring.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, using normal incidence and oblique sweep (~60°–120°) with raking light. Where safe, capture a transmitted-light view to emphasize continuity.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If between panes or laminate-internal by fixed parallax, it is still CAT-5 by location and must be referred.

• CAT-5 (default): Any confirmed thermal stress crack (edge, corner, hole/notch, or hot-spot origin) → Non-Repairable / Out of In-Place Scope. Document extent, apparent growth direction, origin, and proximity to supports/hardware; refer per project protocol (e.g., replacement/manufacturer/engineer).
• Reassign only if no crack is present:
• If examination finds only surface abrasion (no fissure), classify under M.01 (linear scoring) or M.02 (abrasion fields) as appropriate.
• If it is solely edge micro-chips/spalls at a hole/notch without a continuous fissure, use M.06.01 / M.03.04.
• CAT is governed by integrity/location for cracks; acceptance is evaluated separately under VIS §6.

• vs. Linear surface scratch: Scratches exhibit abrasive edges with MSRT catch and chip-flank sparkle; cracks remain phase-stable and should not be stylus-tested.
• vs. Impact star/bullseye (M.04.02): Impact systems have a central nucleus with radial/annular arms; thermal cracks often trace from edges/corners or hot-spot loci without a classic impact nucleus.
• vs. Spontaneous tempered break (Th.03.02): Spontaneous breaks present full fragmentation (“dice”) in fully tempered lites; differential-heating cracks may occur without full fragmentation (until/unless they run).
• vs. Laminate-internal feature / IGU artifact: Use parallax and reflection tracking to confirm ply/cavity location; internal = CAT-5 by location.

1. Safety. Ensure area is safe/stable before close documentation; avoid loading a cracked lite.
2. Photo set (VIS):
3. Overall: 72 in and 36 in, normal incidence, capturing the full fissure path and edges/corners/hardware.
4. Oblique/raking: one or more frames showing continuity and origin; add transmitted-light if safe to confirm depth.
5. Context: frames showing suspected heat source (heater, IR lamp, reflective façade alignment, curtain/blind edge).
6. Record distance/angle in-frame.
7. MSRT note. If recorded, note adjacent SC-class only; do not cross the fissure.
8. Forms: Pane ID; surface numbering; worked surface Y/N; functional coating on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist; photo set attached.
9. Disposition. Mark CAT-5; note estimated length, origin, stability (blunted vs. sharp tip), and nearest supports. Refer per protocol.

Th.03.01 Differential Heating Stress Crack (edge origin) — Continuous fissure observed originating at [edge/corner/hole/notch/hot-spot] on surface #___ under VIS geometry (normal + oblique + raking; transmitted view if safe). MSRT not performed across fissure; adjacent reading noted for context. Classification: CAT-5 (integrity/location). Surface numbering recorded; parallax checked. Photo set + forms attached; acceptance per VIS §6 (separate).

A spontaneous tempered break is a sudden fracture of fully tempered glass with no evident external impact, commonly associated with nickel sulfide (NiS) inclusions or residual/internal stresses. Result is the characteristic fine “dice” fragmentation. Any fractured lite is an integrity condition and is out of in-place restoration scope (CAT-5 by condition/location). This DSS defines identification and documentation only; it does not prescribe repair. Inspect from a safe position under VIS lighting/geometry; record surface numbering and worked-surface status on Forms:

• Pane presents a uniform mosaic of small interlocking fragments (“dice”), often retained by gaskets/pressure plates or an interlayer (if laminated tempered).
• May show a rosette/dense crack nucleus near the suspected inclusion site; sometimes accompanied by a “ticking” sound as stresses equilibrate.
• No clear external impact nucleus (no bullseye/chip), and often no directional hot-particle peppering nearby.
• In IGUs, fragmentation occurs on one ply; the mate ply remains intact.

• Safety / MSRT.
• Treat as unstable; do not perform MSRT. Secure area per site protocol before close documentation.
• Visual signature
• Fine, uniform dice pattern across the pane (distinct from heat-strengthened fracture, which shows larger islands/longer ligaments).
• Absence of impact nucleus or mechanical contact evidence.
• If laminated tempered, offset dice patterns ply-to-ply with interlayer retention.
• Viewing / lighting
• Document at 36 in and 72 in (12 in macros only if safe), normal incidence for overall state and oblique sweep (~60°–120°) to emphasize mosaic density and any suspected origin.
• For IGUs, use parallax/reflection to identify which ply (#1/#2 or #3/#4) has fragmented.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). Note product family (tempered / laminated tempered / IGU).

• CAT-5 (default): Any fractured tempered lite → Non-Repairable / Out of In-Place Scope. Document and refer per project protocol (replacement; manufacturer/engineer review).
• Reassign only if unbroken: If re-inspection shows no fragmentation (e.g., only a crack system), classify under M.07.02 (through-thickness crack) or M.04.02 (impact star) as appropriate—still integrity (CAT-5).
• CAT is governed by integrity/location; acceptance is evaluated separately under VIS-A §6.

• vs. Impact star/bullseye (M.04.02): Impact presents a central nucleus with radial/annular arms; spontaneous break lacks a clear impact origin.
• vs. Heat-strengthened fracture: Heat-strengthened glass forms larger, irregular fragments and longer crack ligaments—dice size is a key discriminator.
• vs. Patterned/etched glass: Decorative patterns lack polygonal, fractured boundaries and loose granules; raking light and gentle observation (no touch) confirm.
• IGU confusion: Ensure you’ve identified which ply has fragmented via parallax; cavity debris/fogging (A.01 family) should be recorded separately.

1. Safety & stabilization. Confirm barricades/support before close approach; avoid loading the fractured lite.
2. Photo set (VIS):
3. Overall: 72 in and 36 in, normal incidence, full pane + framing.
4. Oblique: at least one oblique sweep showing mosaic density and any suspected origin (rosette, edge zone).
5. Detail (if safe): macro of representative fragmentation field; macro of suspected origin area.
6. IGU/laminate: parallax/reflection shot establishing which ply is fragmented.
7. Record distance/angle in-frame.
8. Forms: Pane ID; product family; surface numbering; worked surface Y/N (generally N); reveal status (N/A); lighting/time; geometry checklist; photos attached.
9. Optional fragment survey (off-lite only). If a removed specimen is available and safe to handle, a representative fragment size survey may be recorded for reference; do not attempt on an installed lite.
10. Disposition. Record CAT-5 and notify responsible party per protocol (replacement, temporary shoring, manufacturer/engineer review). Mechanism note “suspected NiS-related spontaneous break” may be included (informative).

Th.03.02 Spontaneous Tempered Break (NiS-related; documentation) — Pane exhibits full “dice” fragmentation on surface #___ / ply [outboard/inboard] under VIS geometry (normal + oblique). No impact nucleus observed. Integrity condition; MSRT not applicable. Classification: CAT-5 (out of in-place scope). Photo set and forms attached; area secured per site protocol; acceptance per VIS-A §6 (separate).

A local heat source imprint is a localized appearance change or crack initiation caused by near-field radiant or convective heating focused on the glass (e.g., space heaters, heat lamps, IR emitters, sun-facing radiant panels). It may present as a tonal/shine shift band or patch, a hot-spot nucleus, or—at higher severities—thermal stress cracking emanating from the heated locus. Classification is appearance-only per VIS (method-agnostic); any confirmed crack is an integrity condition and out of in-place scope (CAT-5). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status on Forms:

• Compact patch or band coincident with the heater footprint, bracket, grille pattern, or lamp geometry; edges are usually soft (no worked transition ring).
• Gloss/contrast shift in specular view; at higher energy, modeled micro-texture may appear within the footprint.
• In severe cases, a crack nucleus forms at or near the hot spot and propagates toward an edge/corner or penetration.
• Context often shows adjacent heater placement, decals/films that focus heat, or furniture blocking airflow.

• Surface-catch class (MSRT)
• SC-0 for optical-only tonal/shine shifts with no relief.
• SC-1 for very shallow modeled micro-texture within the hot footprint; SC-2 is uncommon but possible with pronounced softening.
• Perform one light, non-marring pass; do not stylus across a suspected crack. Prefer polymer stylus on suspected coated faces. MSRT supports classification, not acceptance.
• Visual signature
• Local, non-directional patch or band aligned with a known heat source; no chip flanks or discrete pits typical of hot-particle damage.
• If cracking is present: phase-stable, continuous fissure(s) radiating from the hot locus (see CAT mapping).
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, normal incidence plus oblique sweep (~60°–120°) with raking light to reveal any micro-texture. Document distances/angles in-frame.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If parallax indicates a between-pane presentation, classify CAT-5 by location (out of in-place scope) and refer.
• Mechanism cue (context)
• Proximity/aiming of space heaters, heat lamps, IR panels, blackout drape edges, opaque films/decals, or adjacent radiant elements; note shadow lines or reflector geometries.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth/relief ranges are indicative—measurement is not required.
• CAT-1 (Benign / non-relief): Sheen/tone shift only; SC-0; visible mainly in raking at close/standard view. Indicative relief: ~0–10 µm (optical).
• CAT-2 (Light): Subtle modeled micro-texture within the footprint; SC-1; limited impact at standard view; no chip flanks. Indicative relief: ~10–40 µm.
• CAT-3 (Moderate): Clear detect (SC-2) with visible modeled micro-texture at standard view; boundaries remain soft; no discrete pits. Indicative relief: ~40–120 µm.
• CAT-4 (Severe): Pronounced matte/frosted hot-spot or band due to softening/devitrification; distinct at standard & wide-field views; still no peppering. Indicative relief: ~120–300 µm+.
• CAT-5 (by condition/location): Any confirmed crack emanating from the hot locus, pane instability, or between-pane/inaccessible by parallax → CAT-5 (non-repairable/out of in-place scope).
• CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not “probe” with MSRT.

• vs. Torch proximity streak (Th.02.01): Torch streaks are elongated along a tool path; heater imprints are localized to a fixture footprint or radiant pattern.
• vs. Overheated grinder/belt burn (Th.02.02): Burn lines follow tool travel and may show rubber/compound smear; heater imprints align with stationary radiant geometry.
• vs. Hot-particle damage (Th.01.xx): Slag/sparks present discrete nodules/pits with bright rims; heater imprints are continuous patches/bands without discrete pepper.
• vs. Residue films (R-family): Films remove at reveal and read SC-0; a persisting core patch/band with SC-1/SC-2 indicates thermal imprint.
• vs. Coating anomalies (Co-family): Coating rub/patchiness lacks a heater context; on a worked coated surface any anomaly remains disallowed at acceptance (VIS §6.2.e).

1. Photo set (VIS): 12 / 36 / 72 in, normal + oblique, include raking macros of the footprint; add context frames showing the heater/IR source, mounting position, and distance/aim. Record distance/angle in-frame.
2. MSRT result: Record SC class (SC-0/1/2) with one light, non-marring pass (polymer stylus on suspected coated faces). Do not pass across any crack.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coating-side anomalies on the worked surface remain disqualifying.

Th.03.03 Local Heat Source Imprint (heaters/IR) — Localized radiant hot-spot band/patch on surface #___ with [SC-0/SC-1/SC-2]; no discrete pits or chip flanks; visible at [12/36/72 in] under VIS geometry after Non-Invasive Reveal. Context shows [heater/IR panel/film edge/reflector] near locus. Classification: CAT-[1/2/3/4] by cues; CAT-5 if crack present, pane instability, or between-pane by parallax. Forms + photo set attached; acceptance per VIS-A §6.

A localized thermal “hot spot” imprint is a compact patch or band of appearance change (and, at higher severities, stress damage) produced when reflected or concentrated solar radiation from adjacent surfaces (e.g., concave façades, mirrored fins, metal panels, light shelves, vehicles) focuses on the glass. The result is a tone/shine shift ± modeled micro-texture within the focal footprint; severe events can initiate cracking. Classification is appearance-only per VIS (method-agnostic). Any confirmed crack is an integrity condition and out of in-place scope (CAT-5). Inspect after Non-Invasive Reveal under VIS lighting/geometry; record surface numbering and worked-surface status on Forms:

• Compact elliptic/teardrop patch or narrow wandering band on the sun-exposed elevation, often time-of-day dependent (appears/disappears as the sun moves).
• Sheen/contrast shift in specular view; modeled micro-texture may be present in raking light at the focus.
• Context clues: high-gloss metal, mirrored façades, curved glass, parked vehicles or sunshades positioned to throw a specular reflection onto the lite.
• Severe cases: crack nucleus near the focal hotspot, propagating toward edges/corners/penetrations.

• Surface-catch class (MSRT)
• SC-0 for optical-only impressions (gloss/tone shift without relief).
• SC-1 where very shallow modeled micro-texture exists; SC-2 is uncommon but possible in pronounced softening.
• Perform one light, non-marring pass; use a polymer stylus if a coating is suspected. Do not pass across any suspected crack. MSRT supports classification, not acceptance.
• Visual signature
• Local, soft-edged patch/band—no worked transition ring; lacks discrete pepper (separates from hot-particle damage) and lacks chip-flank sparkle (separates from scoring).
• Often coincident with specular reflection path from a known exterior reflector; may “move” diurnally.
• Viewing / lighting
• Evaluate clean & dry at 12 / 36 / 72 in, with normal incidence and oblique sweep (~60°–120°); include raking light to detect modeled micro-texture. If feasible, document at the expected time of peak reflection.
• Location / access
• Record pane ID and surface numbering (#1–#4; laminate-internal). If parallax indicates a between-pane presentation, classify CAT-5 by location and refer per protocol.
• Mechanism cue (context)
• Identify candidate reflectors/concentrators and geometry (curved/mirrored surfaces, polished metals, cars). Note sun azimuth/elevation and time during observation.

• Assign CAT by appearance + MSRT + morphology (three-part cueing). Depth/relief values below are indicative—measurement is not required.
• CAT-1 (Benign / non-relief): Sheen/tone shift only; SC-0; visible mainly in raking at close/standard view. Indicative relief: ~0–10 µm (optical only).
• CAT-2 (Light): Subtle modeled micro-texture within the hotspot; SC-1; limited impact at standard view; no chip flanks. Indicative relief: ~10–40 µm.
• CAT-3 (Moderate): SC-2 (clear) modeled micro-texture visible at standard view, boundaries soft; no discrete pits. Indicative relief: ~40–120 µm.
• CAT-4 (Severe): Pronounced matte/frosted hotspot or narrow focused band; distinct at standard & wide-field views; still no peppering. Indicative relief: ~120–300 µm+.
• CAT-5 (by condition/location): Any confirmed crack, pane instability, or between-pane/inaccessible by parallax → CAT-5 (non-repairable/out of in-place scope).
• CAT is appearance-based; acceptance is separate under VIS-A at 12/36/72 in. Do not “probe” with MSRT.

• vs. Torch proximity streak (Th.02.01): Torch produces tool-path bands and may leave soot; solar hotspot ties to external reflector geometry and time of day.
• vs. Overheated grinder/belt burn (Th.02.02): Burn lines track abrasive travel and often show compound/rubber smear; solar hotspots are stationary footprints that migrate with the sun.
• vs. Hot-particle damage (Th.01.xx): Slag/spark fields show discrete nodules/pits with bright rims; solar hotspots are continuous patches without pepper.
• vs. Residue films (R-family): Films remove at reveal (SC-0). Persisting core patch with SC-1/SC-2 indicates thermal effect.
• vs. Coating anomalies (Co-family): Coating rub/patchiness may mimic sheen change; on a worked coated surface any anomaly is not permitted at acceptance (VIS §6.2.e). Confirm coating presence and use coated-face rules.

1. Photo set (VIS): 12 / 36 / 72 in, normal + oblique, include raking macros of the hotspot; add context frames showing suspected reflector and the specular path. Record distance/angle/time in-frame; note sun conditions (clear/overcast).
2. MSRT result: Record SC class (SC-0/1/2) with one light, non-marring pass (polymer stylus on suspected coated faces). Do not pass across any crack.
3. 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.
4. Acceptance split: Post-restoration acceptance per VIS-A §6; classification ≠ acceptance. Coating-side anomalies on the worked surface remain disqualifying.

Th.04.01 Localized Thermal “Hot Spot” Imprint (Solar/Reflective) — Soft-edged hotspot/track on surface #___ with [SC-0/SC-1/SC-2]; no pits/craters or chip flanks; visible at [12/36/72 in] under VIS geometry after Non-Invasive Reveal. Context shows [concave façade/mirrored fin/metal panel/vehicle] reflecting to locus; time noted [HH:MM]. Classification: CAT-[1/2/3/4] by cues; CAT-5 if crack present, pane instability, or between-pane by parallax. Forms + photo set attached; acceptance per VIS-A §6.