Prelaminated cement bonded particle board -Specification
2008 Edition

IS 15786 categorizes prelaminated cement bonded particle boards into three types based on their surface abrasion resistance: Type I with high abrasion resistance suitable for heavy-traffic horizontal surfaces like flooring and counters; Type II with moderate abrasion resistance ideal for typical horizontal surfaces such as office or domestic furniture tops; and Type III with low abrasion resistance best suited for vertical applications including wall paneling, partitions, and false ceilings. This classification assists in selecting the appropriate board type according to wear expectations and intended use.

According to IS 15786 Clause 10.9 and its Table 1, prelaminated cement bonded particle boards must meet minimum physical and mechanical criteria such as a density of at least 1250 kg/m³; maximum water absorption of 13% after 2 hours and 25% after 24 hours; maximum thickness swelling of 2% after 2 hours; an average modulus of rupture (MOR) of 9.0 N/mm² with a minimum of 7.5 N/mm²; an average modulus of elasticity (MOE) of 3000 N/mm² with a minimum of 2550 N/mm²; minimum tensile strength perpendicular to the surface of 0.2 N/mm², reduced to 0.10 N/mm² after accelerated water resistance testing; screw withdrawal strengths of 1250 N on face and 850 N on edge; and abrasion resistance measured in revolutions of 450, 250, and 75 for Types I, II, and III respectively. Testing includes boiling specimens for 2 hours followed by drying to approximately 12% moisture before tensile strength evaluation, and abrasion resistance determined through controlled abrasion until surface wear.

The abrasion resistance test under IS 15786 (Clause 10.10 and Annex B) involves rotating a specimen against two weighted abrasive wheels covered with abrasive paper, abrading an annular surface area. The specimen is inspected every 25 revolutions, with abrasive paper replaced as needed. Testing continues until 95% of the laminated surface is worn through to the particle board beneath, marking the failure point. The number of revolutions at this point is recorded, and the abrasion resistance value is calculated as half of the revolutions counted. Results from three specimens are averaged and rounded to the nearest 25 revolutions. This method classifies boards into Type I (minimum 450 revolutions), Type II (250 revolutions), and Type III (75 revolutions), guiding their appropriate application based on surface durability.

IS 15786 Clause 8.3 specifies dimensional tolerances for prelaminated cement bonded particle boards as ±5 mm for length and width. Thickness tolerances depend on the board thickness and surface treatment: for unsanded boards between 6 and 12 mm, the tolerance is ±1 mm; for boards from 12 to 20 mm, ±1.5 mm; and for boards thicker than 20 mm, ±2 mm. Standard board sizes include lengths of 3050 mm or 2440 mm and a width of 1220 mm, with thickness options ranging from 6 mm up to 40 mm. Custom dimensions can be mutually agreed upon by manufacturer and purchaser to meet specific requirements.

Per IS 15786, manufacturers are required to mark each prelaminated cement bonded particle board legibly and indelibly on any edge or surface with details including the manufacturer’s name or trademark, the board type, thickness, and the date of manufacture. Additionally, products may bear the BIS Standard Mark subject to licensing under the Bureau of Indian Standards Act, 1986. Use of this certification mark indicates compliance with the standard’s quality and testing criteria. Manufacturers must acquire appropriate BIS authorization to affix this mark, ensuring traceability and adherence to the prescribed specifications.