Materials for Use In The Manufacture of Magnesium Oxychloride Flooring Compositions
1982 Edition

The standard covers grading requirements for fillers and aggregates tailored to various flooring classifications (sections 4.1.4, 4.2.4, 4.3.1), as detailed in Table 3, which specifies sieve sizes and percentage passing for materials such as wood flour, asbestos fibers, sand, talc, and marble powder across different flooring applications like general purpose, heavy duty, non-slip, mosaic, terrazzo, industrial granolithic, and base coatings. Sampling and conformity for magnesium chloride and pigments are also mandated per relevant clauses, ensuring particle size distribution aligns with intended flooring performance and durability.

Chemical composition requirements stipulate a minimum of 87% magnesium oxide (MgO) by weight, maximum 2.5% calcium oxide (CaO), maximum 2.5% carbon dioxide (CO2), and loss on ignition not exceeding 8%. The combined total of MgO, CaO, aluminum oxide, silicon oxide, and loss on ignition shall be at least 99.5%. Physically, calcined magnesite must have a bulk density between 0.65 and 0.85 kg/l, with fineness requirements demanding at least 97% passing through a 150 micron sieve and 95% through a 75 micron sieve. Setting times range from 3 to 6 hours initially and 7 to 15 hours finally, while strength is measured via modulus of rupture with minimum values of 7 N/m² at 7 days and 10.5 N/m² at 28 days. Dimensional stability limits include a maximum linear expansion of 0.15% and contraction of 0.25%. All testing follows IS 10032-1982 and IS 450 (Part I)-1978.

Magnesium chloride utilized must adhere to Grade 3 specifications as defined in IS 254:1973 to guarantee appropriate purity and suitability for magnesium oxychloride flooring production. This grade ensures chemical consistency and physical properties required for optimal flooring performance. Physical characteristics of associated calcined magnesite are also referenced to IS standards, with parameters such as bulk density, fineness, setting time, strength, and dimensional changes clearly defined.

The standard identifies several types of fillers and aggregates including marble powder, talc, ground silica, sand, crushed stone, quartz, emery, fused abrasives, marble and granite chips, and asbestos fibers. These must be chemically inert relative to other flooring components. Grading criteria specify sieve sizes and allowable passing percentages for different flooring types as detailed in Table 3. Sampling protocols require specified weights for calcined magnesite, wood flour, sawdust, and other fillers from multiple sub-samples to ensure representative testing. Special notes include maximum chip size limits relative to finished floor thickness.

Permissible pigments for coloring the flooring compositions must conform to designated Indian Standards depending on color: black, red, and brown pigments correspond to IS 44-1969 and IS 3574 (Part II)-1966; green to IS 54-1950; yellow to IS 50-1967 and IS 3574 (Part II)-1966; blue to IS 55-1970, IS 56-1975, and IS 3574 (Part II)-1966; white to IS 411-1968. Pigments must be free of adverse chemical reactions with flooring materials and maintain physical stability. Sampling requires dry, airtight containment and testing within four weeks according to relevant IS norms.

Calcined magnesite must be packed in jute bags lined internally with bitumen and polythene films to prevent moisture ingress, with each bag ideally holding 50 kg. Chemical and physical property requirements are reiterated here to ensure material integrity during storage and transport. Testing procedures and specifications for strength and dimensional stability are also described to maintain quality assurance.

Sampling must be representative and involve combining at least ten equal sub-samples taken evenly from bulk or packaged consignments. Minimum sample weights include 0.5 kg for calcined magnesite, 3 kg for wood flour or sawdust, and 7 kg for other fillers. The number of packages to be sampled depends on consignment size, ranging from 10% sampling for up to 100 packages to 3% for consignments exceeding 1000 packages, with minimum numbers specified. If fewer than ten packages exist, all must be sampled. Sampling procedures ensure statistically valid and reliable test results.

Use of the Standard Mark under IS 657 is regulated by the Bureau of Indian Standards Act, 1986. Manufacturers must acquire a license from BIS to apply the mark, confirming compliance with the standard. Licensing details and contacts are provided for BIS headquarters, central laboratory, regional, and branch offices across India. The certification mark signifies quality assurance and adherence to Indian Standards, facilitating market acceptance.