DSS-Th.02.01 — Torch Proximity Streaking (Heat Skid / Thermal Streaks)

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.

• 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.
• MSRT result: Record SC-class (SC-0/1/2) with one light, non-marring pass (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. 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.