Smoke developed index

The surface burning characteristics (flame spread index and smoke developed index) for wood and wood products as measured by American Society for Testing and Materials (44) can be reduced with fire retardant treatments, either chemical impregnation or coatings (48). Fire retardant treatments also reduce the heat release rate of a burning piece of wood (49,50). The heat release rates (51) of the burning materials are an important factor in fire growth. 

The classification of linings in the U.S. model building codes is based on the FSI and SDI (smoke developed index). The latter is based on the area under the light transmission versus time curve normalized to the area for red oak flooring, which by definition has an SDI of 100. There are three classes Class A for products with FSI < 25, Class B for products with 25 < FSI < 75, and Class C for products with 75 < FSI < 200. In all cases, the SDI must be 450 or less. Class A products are generally permitted in enclosed vertical exits. Class B products can be used in exit access corridors and Class C products are allowed in other rooms and areas. 

The laminate construction in FRP parts can have an effect on flame spread and smoke test results. A study was conducted by Stevens15 and published in the proceedings of Composites 2007 conference. This study looked at how glass fiber content and panel thickness affected the ASTM E-84 flame spread index (FSI) and smoke developed index (SDI). The effects of fiber content and thickness on cone calorimeter results were also evaluated. Another study was conducted by Dempsey16 looking at the effect of glass content in several fire tests, and in this paper, he also found a correlation between the FR performance and glass content. 

ASTM E84-00a)a Flame spread index = 10 Smoke development index = 15... 

Fire tests in a 25-foot tunnel furnace were carried out according to standard ASTM E84 by the Underwriters Laboratory and the Hardwood Plywood and Veneer Association. Results are given for the flame spread index (FSI) and smoke developed index (SDI). The values obtained from burning the test materials represent a comparison with that of Va inch inorganic reinforced cement board expressed as zero and red oak flooring expressed as 100. 

In the same 25-ft tunnel test the so-called smoke development index (SDI) can also be determined. The smoke measurement is based on the percentage of retardation of light passing through the tunnel exhaust stream and detected by a photocell, and then data obtained are converted to the SDI, with red oak flooring set at 100. AC 174 does not specify any particular SDI as the code requirement, but the industry generally considers SDI above 450 as hazardous and not acceptable, particularly for interior flnish. 

Species Flame spread index Smoke developed index... 

SMOKE AND TOXIC GASES, AND SMOKE DEVELOPMENT INDEX... 

TABLE 14.6 Smoke developed indexes for commercial WPCs, determined according to ASTM E 84... 

Deck boards (solid or hollow) Profile Manufacturer Principal ingredients Smoke development index... 

Generally, but not necessarily, the higher the FSI, the higher the smoke developed index (SDI) (see Table 14.1). For wood the SDI is typically between 60 and 230. WPCs also often exceed these values (see Table 14.6). 

TABLE 14.15 Smoke Development Index (SDI) determined in flaming and nonflaming conditions according to ASTM E 662, for two HDPE-based composite materials, one filled with rice hulls, another with rice hulls and a mineral filler. Detailed on the compositions are given on page 484. Data by the author. 

Slip resistance, 24, 369, 371, 376, 381 definitions, 369 effect of formulation, 381 plastics, 371 wood decks, 373 Slip-stick, 658 Smoke and toxic gases, 467 Smoke developed index (SDl), 462, 468,... 

Class A Interior Wall and Ceiling Finish flame spread index (FSI), 0 to 25 smoke developed index (SDI), 0 to 450... 

Table 11.26 Estimated Fire Propagation Index and Smoke Development Index for Polymers from Parts of a Minivan ...

The smoke generation characteristic of polymers during fire propagation is expressed by a smoke development index (SDI) [21, 22,40, 83]. The SDI concept... 

Figure 11.16. Relationship between smoke release rate and smoke development index for polymers. Data were measured in our laboratory in ASTM E2058 Fire Propagation...

In the test, measurements are made for the percent light obscuration by smoke flowing through the exhaust duct, gas temperature (7.0-m/23-ft from the burner) and location of the leading edge of the flame (visual measurement) as functions of time. The measured data are used to calculate the flame spread index (FSI) and smoke developed index (SDI) from the flame spread distance-time and percent light absorption-time areas, respectively. Some typical FSI values are listed in Table 53.16 taken from Ref. 46. 

The measurements consist of flame spread over the surface and light absorption in the exhaust duct of the timnel. Test duration is 10 min. A flame-spread index (FSI) is calculated on the basis of the area under the curve of flame tip location versus time. The FSI is 0 for an inert board, and is normalized to approximately 100 for red oak flooring. The smoke developed index (SDI) is equal to 100 times the ratio of the area under the curve of light absorption versus time for the 10-min test duration to the area under the curve for red oak flooring. Thus, the SDI of red oak flooring is 100, by definition. 

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