What is class A 1 fire rating?
The definition of a Class 1 Fire Rating is the flame spread index and smoke development index, which really means how fast the flame spreads when introduced to the insulation material and how much smoke it produces. The Class A or Class 1 Fire Rating is the best an insulation material can receive.
What is a Class 1 building material?
Frame (Class 1): Buildings where the exterior walls are wood or other combustible materials, including construction where combustible materials are combined with other materials (such as brick veneer, stone veneer, wood iron-clad, stucco on wood).
What is ASTM e84 Class A Class 1?
Material classification of fire performance is based on the test results in accordance with the Life Safety Code, NFPA 101 Section 10.2….ASTM E84 Acceptance Criteria.
| Class | Flame Spread Index | Smoke Development Rating |
|---|---|---|
| Class 1 or A | 0 – 25 | 450 maximum |
| Class 2 or B | 26 – 75 | 450 maximum |
| Class 3 or C | 76-200 | 450 maximum |
What is class A construction type?
Class A: Fireproof Structural Steel Frame The primary feature of class A buildings is the fireproofed structural steel frame, which may be welded, bolted or riveted together. The fireproofing may be masonry, poured concrete, plaster, sprayed fiber or any other method, which gives a high fire-resistance rating.
What is fire rated drywall?
Fire-rated drywall is drywall that is thicker than standard sheets and which sometimes comes with extra additives to the gypsum core such as fiberglass. The purpose of fire-rated drywall is to slow the progress of fire to give inhabitants enough time to escape.
How long is Class A fire rating?
Class A – Flame-spread 0-25, smoke developed 0-450. Class B – Flame-spread 26-75, smoke developed 0-450. Class C – Flame-spread 76-200, smoke developed 0-450….Exterior Wall Construction.
| Description of Finish | Time (minutes) |
|---|---|
| 5/8-inch Type X gypsum wallboard | 40 |
| Double 3/8-inch gypsum wallboard | 25 |
What is fire rating of ASTM E84?
One-Hour Fire-Rated Having a Class A rating generally refers to the ASTM E84 standard for flame spread and smoke generation. But a one-hour rated wall generally is required to comply with the E84 Class A rating requirements as well.