Rubber Flooring Materials For General Purposes
1992 Edition

According to IS 809 (1992), rubber flooring tiles are produced in standard sizes of 200 × 200 mm, 300 × 300 mm, and 500 × 500 mm. Thickness may vary with no fixed limitation; for ribbed or fluted tiles, thickness refers to the base rubber layer. Though the standard does not explicitly state numerical tolerances, common practice suggests thickness tolerance of ±0.5 mm or ±5% of the nominal thickness, whichever is smaller, and size tolerance for length and width is ±1.0 mm. Squareness is typically maintained within ±1 mm per 300 mm length. For exact values and conformity, refer to Annex G or consult with manufacturers.

The water absorption test under IS 809 involves cutting a specimen of 100 mm × 100 mm with clean edges, weighing it to the nearest milligram (denoted as P1), and immersing it in distilled water at 27 ± 2°C for 24 hours. After immersion, the specimen is surface-dried with filter paper and weighed immediately (P2). Water absorption percentage is then calculated as ((P2 - P1) / P1) × 100. The maximum permissible water absorption is 0.5% by weight. The lot passes the test if the number of defective sheets remains within the permissible limits defined in Table 3 of IS 809.

IS 809 specifies a hardness range between 65 IRHD to 96 IRHD for rubber flooring materials. Hardness is measured using the International Rubber Hardness Degree (IRHD) method described in IS 3400 (Part 2):1980, which involves assessing indentation depth under a prescribed load using a durometer. Values are rounded according to IS 2:1960. Maintaining this hardness range ensures the flooring is neither too soft nor excessively hard, optimizing durability and comfort. Flooring thickness typically ranges from 3 to 6 mm, and materials must be free of defects such as blisters or cracks.

Sampling for rubber flooring materials under IS 809 is conducted randomly in accordance with IS 4905:1968. The number of sheets or tiles sampled depends on lot size and follows the sampling plans specified in Tables 3 and 4 of IS 809. Tests include hardness, abrasion resistance, compression set, and other physical properties. Each sampled sheet or tile must meet all specified requirements; if any defect is found, that unit is considered defective. A lot is accepted if the total defective units do not exceed the permissible number indicated in the standard. Marking and conformity assessments follow this sampling framework.

IS 809 permits the optional application of the Standard Mark on rubber flooring sheets, rolls, or tiles to indicate compliance with the standard. However, explicit packing requirements are not detailed in the standard text provided. In practice, packing is typically done using protective materials such as hessian cloth and wooden crates to prevent damage during handling and transportation. Marking usually includes manufacturer identification, product dimensions, thickness, and manufacturing year. For detailed packing procedures, industry best practices are generally followed.