DSS-M.05.03 — Wash-Line Scratch Bands

Parallel, height-consistent bands of linear surface scoring produced when particulates or trapped fines are carried across the lite by factory washing/handling equipment prior to or after heat-treating. Bands typically align perpendicular to glass travel and traverse significant widths of the face. Classification is appearance-based under VIS inspection conditions; acceptance is governed separately by VIS-A. Use VIS inspection geometry and documentation conventions.

• Parallel stripes/belts of fine to moderate scratches at repeatable elevations across adjacent lites from the same batch/run.
• Lines read strongest in raking light; at standard view, bands may collapse into a faint “striped haze” when shallow.
• Often span long distances, intersecting mullion reflections; individual lines within a band can vary in prominence.
• May co-occur with other FD manifestations (e.g., long FD fields) on the same elevation.

• MSRT (Manual Surface-Relief Test) class - one light, non-marring pass only:
• SC-1 (slight) for shallow band sets;
• SC-2 (clear) where chip flanks are present on stronger lines. Numeric depth is not required for classification; prioritize MSRT class + morphology.
• Visual signature - multiple, co-planar lines forming a belt; some lines show clean edges, others exhibit micro-chipping/chip flanks under raking light. (Use VIS §5 lighting/geometry.)
• Viewing & lighting - Capture at 12 / 36 / 72 in; normal + oblique sweep; include raking-light frames. Surfaces clean/dry per VIS “Non-Invasive Reveal.”
• Location / access - Present on the exposed face being evaluated. Where fixed parallax proves a between-pane condition, classify CAT-5 (out of in-place scope) and refer per project protocol.

(Informative micrometer ranges are for context; classification does not require measurement.)

• vs. Long FD scratch field (M.05.02) - fields may wander; wash-line bands are elevation-consistent, often repeating across lites. (M.05 indexing.)
• vs. Conveyor/belt line scoring (M.01.04) - M.01.04 typically produces one or a few straight, travel-aligned tracks; wash-line bands present as stacked belts of lines at a set height.
• vs. Squeegee burn lines (M.02.05) - squeegee burns are friction films (haze) with SC-0 to SC-1 and no chip flanks; wash-line bands show line relief and may present chip flanks.
• vs. Coating rub/patchiness (Co.01/Co.03) - coating anomalies are worked-surface appearance changes and are not permitted at acceptance on coated faces; wash-line bands are mechanical lineations in the glass surface. Apply VIS §6.2.e where coatings are involved.
• vs. Factory optical features (e.g., roller wave, ream/cord) - optical features are pane-scale, SC-0, and lack line relief/chip flanks; do not spot-work factory optical patterns per VIS.

• Photo set (VIS): 12/36/72 in; normal + oblique; include raking. Capture at least one context frame across adjacent lites to show height-repeat and one macro with chip-flank detail.
• MSRT result: Record SC-class (SC-1 / SC-2). Single non-marring pass; on suspected coated faces, prefer polymer stylus.
• Forms/Logs: Pane ID; surface numbering; worked surface Y/N; functional coating present on worked surface? (Y/N/Unknown); reveal status; lighting/time; geometry checklist.
• Scope split: Classification under VIS-DA (this DSS); post-restoration acceptance under VIS-A-do not conflate factory features with acceptance criteria.

• Treating band haze as a film only (R-series) and skipping MSRT-misses line relief and chip flanks diagnostic of FD.
• Attempting localized “spot-buffs” that create a transition edge; VIS disallows visible worked boundaries at acceptance.

• M.05.03 Wash-Line Scratch Bands - Parallel, elevation-consistent bands of linear scoring observed under VIS geometry; MSRT = SC-1/SC-2 with chip-flank morphology on primary lines. Classified CAT-2 / CAT-3 / CAT-4 by cue set as documented. If fixed parallax indicates a between-pane condition, record CAT-5 and refer per project protocol.