AMSCO Windows Glass Inspection Criteria
QUALITY CLASSIFICATIONS
Monolithic glass products used for and produced by AMSCO Windows conform to the following industry standards and specifications:
- ASTM C 1036 - Standard Specification for Flat Glass (Q3/Glazing Select)
- ASTM C 1048 - Standard Specification for Heat-Treated Flat Glass
- ASTM C 1376 - Standard Specification for Pyrolytic and Vacuum Deposition Coatings on Flat Glass (Kind CV specification)
- IGMA 3100 - Voluntary Guidelines for the Identification of Visual Obstructions in the Air Space of Insulating Glass Units
VISUAL INSPECTION CRITERIA
Vision Windows:
- Glass in which the lower edge is a maximum of 6 ft (1.8 m) above the viewer’s floor level.
- Viewing distance of 3 ft for the central viewing area and 10 ft for the border area.
Overhead Windows:
- Glass in which the lower edge is more than 6 ft (1.8 m) above (the viewer’s) floor level or cannot be approached within 10 ft (3.0 m), the glass is usually sloping from the vertical plane.
- Viewing distance of 10 ft for the central viewing area and 15 ft for the border area.
Central Viewing Area: Is 80% of the length and 80% of the width dimensions centered on the glass.
Border Area: The edge of the lite outside the central viewing area.
Blemishes for coated glass shall be inspected to the following criteria:
- In transmission with 20/20 vision (naked eye or corrected)
- A viewing angle of 90 degrees to the specimen
- Lighting needs to be a bright uniform background either daylight (without direct sunlight), or a diffused light panel (minimum 1700 lux) simulating daylight. AMSCO Windows recommends a minimum distance of 1 ft between the glass and diffuse light panel.
If a blemish is readily apparent under these viewing conditions, the below criteria under “Allowable Blemishes” applies. If the blemish is not readily apparent under these viewing conditions, the window should be accepted as is.
ASTM 1036: Viewing Conditions for Blemish Detection
3ft Central Viewing Area.10ft Border Area.
INSPECTION CRITERIA
| Coating | Must be uniform when viewing using a visual inspection criteria stated below |
| Dimension | ±1/16” on all annealed cut size products and ±1/16” on all stock & tempered glass |
| Bow | 1/16" per linear foot for all tempered products |
| Glass Thickness | Per ASTM |
ALLOWABLE BLEMISHES
If a blemish is apparent under the outlined viewing conditions, the following criteria applies:
| Allowable blemish size | Allowable blemish size | |
| Coating Defect Type | Central Viewing Area | Border Viewing Area |
| Pinhole, Debris, Dirt, Spots | 1/16" or 1.6 mm. No more than 5 allowed in a 12" | 3/32" or 2.4 mm |
| Coating Scratch | 1" or 25 mm max length | 3" or 75 mm max length |
| Coating Rub | Not allowed | Length plus width not to exceed 3/4" or 19 mm |
| Corrosion | Not allowed | Not allowed |
| Arcing/Crazing | Less than or equal to 1/2", on edge only | Less than or equal to 1/2", on edge only |
| Chips - Shell | No more than 1/4" wide by 1/4" long and less than 1/2 the thickness of the glass in depth. No more than one per side | No more than 1/4" wide by 1/4" long and less than 1/2 the thickness of the glass in depth. No more than one per side |
| Chips - Adhesive | None allowed | None allowed |
| Chips - Flake | < 1/64", no limit | < 1/64", no limit |
| Corners | Flares are allowed within the dimensional tolerance of the unit | Flares are allowed within the dimensional tolerance of the unit |
| Corner Off | Up to 1/4" if edge surface is smooth. Rough damage is not allowed | Up to 1/4" if edge surface is smooth. Rough damage is not allowed |
| Seeds, Bubbles, Knots, Stones | Must be 1/16" or less, must be separated by 24" | Must be 1/16" or less, must be separated by 24" |
Observation Limits
Observation Duration| Unit Size | Maximum Observation Duration | |
|
5 seconds | |
| 6 - 25 ft2 | 10 seconds | |
| > 25 ft2 | 20 seconds |
When viewing the coatings for blemishes the glass is divided in two areas: Central Area & Outer Area. Each area has different blemish criteria.