Sheet glass, distinguished by its transparent nature and flat, glossy finish, possesses a smooth surface that may exhibit a subtle waviness. This characteristic makes it ideal for various applications, including glazing and framing, thanks to its distinct properties.

As Per IS 2835:1987, sheet glass is categorized into four distinct qualities:

1. AA Quality or Special Selected Quality (SSQ) – Intended for use where superior quality safety glass, high-quality mirrors, photographic plates, projection slides, etc., are required.

2. A Quality or Selected Quality (SQ) – Designed for particular applications such as glazing, mirror production, safety glass, and more.

3. B Quality or Ordinary Quality (OQ) – Designed for applications in glazing and framing purposes.

4. C Qualify or Greenhouse Quality (GQ) – Designed for various applications including greenhouse glazing, production of frosted glass, flooring strips, and more.

Sheet glass is required to meet specific criteria: it must be flat, transparent, and clear, with a possible light tint when viewed from the edge. Additionally, it must be crack-free and adhere to the standard's specifications regarding nominal thickness, thickness range, and dimensional tolerance for cut sizes (length and width).

TESTS

The subsequent test must be conducted for glass sheet.

• Dimension

• Bow

• Thickness

• Scratches, Rubs and Crush

• Reams, strings, and lines

• Waviness test

An appropriately maintained laboratory is necessary for conducting various tests according to the methods outlined in the standard. Each quality requires testing on a separate sample to ensure accurate results.

Packaging and labeling procedures must align with the standard requirements. Each package containing sheet glass should be clearly marked with essential details such as material name and quality, nominal thickness, manufacturer's name or trademark, and a code or serial number as per the standard guidelines. Additionally, packaging may feature the standard mark (ISI Mark) when applicable. To utilize the ISI Mark, manufacturers must obtain a BIS license from the Bureau of Indian Standards, which involves a thorough assessment of manufacturing infrastructure, quality control measures, testing capabilities, and production processes.

PROCESS FOR BIS ISI MARK CERTIFICATION