The most commonly used types of plywood are commercial grade, boiling waterproof grade (BWP) or marine grade ply. However, fire resistance is of equal importance because it can make all the difference at critical times. As such, when you get your homes furnished, it is a wise choice to insist on FR grade ply. What exactly is fire retardant ply?
Wood is inflammable and adhesives used in commercial grade engineered wood may promote the flame. BWP and marine grade plywood are melamine or phenolic resin impregnated which does reduce flammability. However, true FR grade ply must conform to IS 5509 specifications and be tested to IS 1734 (part 3) specs. Additionally, it must also comply with IS 303 BWR grade specifications.
Furthermore, certain chemicals are added during the manufacturing process to delay the plywood from catching fire and during this time, you can take steps to control the flame or evacuate the house. Additives reduce tendency of plywood to spark and ignite easily. These additives also slow down the rate of combustion and prevent spread of burning over the surface of the treated FR stuff. Such treatments also reduce smoke generation.
The methodology applied to make FR grade ply includes the pressure impregnation of it in vacuum with chemicals after it has been manufactured. This ensures deeper penetration of the fire retardant solution. This is the best type of FR grade you should choose. Look for the appropriate BIS marking on each sheet to ensure it is FR grade.