PASSIVE FIRE PROTECTION – How It Works?
Plywood and OSB (oriented strand board) structural panels are real wood, a natural insulator, and therefore provide good protection against heat loss and condensation. Large panel size also minimizes the number of joints that can “leak” heat, airborne noise or flames.
Flame Spread and Smoke Generation
Flame spread of the interior finish is a concept that relates to the rate at which a flame will spread along the surface of a material.
The various regional and city building-code bodies have adopted flame-spread limitations for interior finish material based on recognized laboratory test methods. The lowest flame-spread rate (0 to 25) is permitted for areas where fire hazard is most severe.
Flame-spread ratings for various materials are given in the table below.
Material | Flame Spread Rating |
Asbestos-cement board | 0 |
Fire-retardant treated softwood plywood | 25 or less |
Fire-retardant-coated softwood plywood | 25 or less |
Fire-retardant-treated lumber | 25 or less |
Oak lumber | 100 |
PS 1 construction plywood | 75-200 |
OSB | 74-200 |
Fire – Retardant Treatment
Plywood & OSB pressure-impregnated by MIVIKO with Nano fire-retardant liquid is able to inhibit combustion, achieving a flame spread of 25 or less (really less than 10) when subjected to a 30-minute test. Fire-retardant plywood & OSB are non-harmful and non-hazardous materials.
