Bis Standards For Continuous (Piano) hinges The Bureau of Indian Standards (BIS) has defined Continuous (Piano) Hinges, IS 3818:1992, long and narrow type of hinges generally used on doors, cabinets, and enclosures that need to be supported along the length of the joint for simplifies operation. It specifies the material, size, and performance factors that make the products durable, easy to operate, and safe to use. After adoption of IS 3818:1992, any manufacturer of continuous hinges must first obtain BIS certification before selling their products in India. This stamp of certification assures that the hinges meet the tested and accepted standards of quality and performance for India which builds trust and reliance among consumers. The products under this standard must be marked as ISI Mark which means Indian Standards have been met and tests for the hinges proved the quality.