How to Read a Plywood ISI Mark: What the Numbers Mean

IS:303 is the Indian Standard for moisture-resistant plywood. If you see this mark on a plywood sheet, it means the plywood has been tested and certified for moderate moisture resistance — suitable for indoor furniture in dry areas. This is the most common grade and the most affordable. The ISI mark should be stamped on every sheet, not just the packaging.

IS:710 covers both BWR (Boiling Water Resistant) and Marine (Boiling Water Proof) plywood. The distinction between BWR and Marine is in the test duration and bonding standard applied. Both are marked IS:710 but the grade (BWR or Marine/BWP) should be clearly mentioned. Use IS:710 plywood for kitchens, bathrooms, and any moisture-prone areas.

IS:1659 is the standard for block boards — solid wood strips sandwiched between veneer layers. Block boards are used for large surface applications like table tops, doors, and partitions where a flat, rigid panel is needed. They're more dimensionally stable than plywood for large unsupported spans.

Counterfeit plywood is a significant problem. Check: the ISI mark should be embossed or printed on the plywood surface (not just on a sticker). Look for the CM/L number (license number) — you can verify this on the BIS website. Buy from authorised brand dealers. If the price seems too good to be true, it probably is. HandyPanda sources only ISI-certified plywood from authorised distributors — guaranteed genuine, delivered across Gurgaon.