What does a smoke developed rating indicate?
Table of Contents
- 1 What does a smoke developed rating indicate?
- 2 What does a flame spread index of 25 mean?
- 3 What is a flame index?
- 4 What is the difference between Class A and Class C fire rating?
- 5 How are flame-spread ratings established?
- 6 What are flame-spread classifications?
- 7 What is class A 1 fire rating?
- 8 How are flame spread rating established?
- 9 What is the meaning of smoke-developed index?
- 10 What is the ASTM E84 smoke-developed index?
- 11 What is the Dispersion Index of smoke?
What does a smoke developed rating indicate?
Smoke-developed index (abbreviated SDI) is a measure of the concentration of smoke a material emits as it burns. Like the Flame Spread Index, it is based on an arbitrary scale in which asbestos-cement board has a value of 0, and red oak wood has 100.
What does a flame spread index of 25 mean?
A numerical reference that measures how fast and far a flame spreads during a 10-minute test. CLASS A = Flame Spread Index of 25 or less; the best possible rating, awarded to fire-retardant building products, like concrete.
What is a 25 50 fire rating?
The flame spread and smoke developed index results are reported on a scale from 0 (cement board) and 100 (red oak). The flame spread index (FSI) for pipe and duct insulation used in an air plenum must be 25 or less and smoke developed index (SDI) 50 or less, commonly referred to as “25/50” rated.
What is a flame index?
Flame index is where a premixed flamelet exists and is at the location of a non-premixed flamelet. A new method to measure flame index was developed that adds NO2 to the air; acetone is used as one component of the fuel.
What is the difference between Class A and Class C fire rating?
Class A fire retardants have a flame spread rating of between zero and 25. These materials are effective against severe fire exposure. Class C fire retardants have a flame spread rating of between 76 and 200. These materials are effective against light fire exposure.
What does class 3 flame spread rating mean?
between 76 and 200
A Class C or Class 3 fire rating has a flame spread rating between 76 and 200. This rating incorporates building materials like plywood, fiberboard, and hardboard siding panels. It also includes any of the faster burning whole woods.
How are flame-spread ratings established?
From these observations a flame spread rating can be calculated. For example, if the flame travels 19-1/2 feet in less than 5-1/2 minutes (the time required for flame to spread on 19-1/2 feet of red oak), the rating is 100 times 5-1/2 divided by the time (minutes) in which flame spreads 19-1/2 feet on the sample.
What are flame-spread classifications?
The most commonly used flame-spread classifications are: Class I or A, with a 0-25 FSR; Class II or B with a 26-75 FSR; and Class III or C with a 76-200 FSR. Class B – Flame-spread 26-75, smoke developed 0-450. Class C – Flame-spread 76-200, smoke developed 0-450.
Is UL 723 the same as ASTM E84?
(UL) developed UL 723 (now called ANSI/UL 723) and the American Society for Testing and Materials (ASTM) has adopted this UL test into its own standard as ASTM E84. This industry standard outlines the test procedure for evaluating surface burning characteristics of interior wall finish materials.
What is class A 1 fire rating?
A class 1 fire rating is the best fire rating of materials that can be achieved. Class A fire ratings indicate a flame spread rating somewhere between zero and 25. Materials that fall into Class A or Class 1 include things like brick, gypsum wallboard, and fiber cement exterior materials.
How are flame spread rating established?
The most commonly used flame-spread classifications are: Class I or A, with a 0-25 FSR; Class II or B with a 26-75 FSR; and Class III or C with a 76-200 FSR….Exterior Wall Construction.
| Description of Finish | Time (minutes) |
|---|---|
| 1/2-inch gypsum wallboard | 15 |
| 5/8-inch gypsum wallboard | 30 |
| 1/2-inch Type X gypsum wallboard | 25 |
What is class 3 flame rating?
What is a Class C or Class 3 fire rating? A Class C or Class 3 fire rating has a flame spread rating between 76 and 200. This rating incorporates building materials like plywood, fiberboard, and hardboard siding panels. It also includes any of the faster burning whole woods.
What is the meaning of smoke-developed index?
Smoke-developed index. Smoke-developed index (abbreviated SDI) is a measure of the concentration of smoke a material emits as it burns.
What is the ASTM E84 smoke-developed index?
The ASTM standard E84 defines a standard test method for surface flame spread and smoke density measurements. A smoke-developed index of less than 450 is required by IBC section 803.1 at interior walls and ceilings for all surface materials except trim. ^ “Archived copy” (PDF).
What is the smoke-developed index of wall and ceiling finish?
Wall and ceiling finishes shall have a smoke-developed index of not greater than 450. Tests shall be made in accordance with ASTM E84 or UL 723.
What is the Dispersion Index of smoke?
The Dispersion Index is a numerical indicator of how well and how rapidly smoke will be dispersed. It utilizes stability, mixing height, and transport wind as the major factors. Other factors are: the amount and angle of sunlight and temperature. Most states include some type of dispersion (or stagnation) index in their weather forecast.