Assessment of the visual quality of glass products

Glass products are subject to strict quality control.

The guideline is valid to a limited extent for special insulating glass, such as insulating glass with glazing bars, bulletproof and fireproof glazing.

When assessing built-in glass, it should generally be assumed that in addition to visual quality, important features of the product that fulfill its function should also be taken into account.

Permissible glass defects in the field of view (except for the 20 mm wide peripheral strip of the product).

In the marginal zone, glass mass losses of up to 5 mm and a thickness of up to 10% of the nominal glass thickness are permissible. Glass corners may have additional dimensional deviations of +/- 20 mm.

*Point defects smaller than 0.5 mm are not taken into account. Defects of 0.5-1.0 mm cannot occur in a cluster, i.e. a minimum of four defects at a distance of up to 200 mm from each other (for double-layer glass).

** Hairline scratches are not taken into account.

The assessment of the visual quality of glass products is carried out according to the description presented in the standards PN-EN ISO 12 543-6, PN-EN 1096, PN EN 1086-1.

During the examination, defects visible from a distance of 300 cm in the case of products containing coated glass and 200 cm in the case of other glass products (glasses) , against the background of a matte gray screen in normal lighting conditions, are taken into account.