NYC-WTC_000209333

NYC 9/11 Public Portal Document

( D575S

smaller components without losing its fibrous propenies or 5. Significance and Usa appearance. 5.1 This microvaewum sampling and indirect analysis 12 Descriptiom qf Terms Specific to This Standard method is used for the general testing of non-airborne dust 3.2.1 aspect r«io—the ratio of the length of a fibrous samples for asbestos. It is used to assist in the evaluation of particle to its average width. dust that may be found on surfaces in buildings such as 3.2.2 bundle—» structure composed of three or more ceiling tiles, shelving, electrical components, duct work, fibers in a parallel arrangement with the fibers closer than carpet, etc. This test method provides an index of the one fiber diameter to each other, concentration of asbestos structures in the dust per unit area 3.2.3 cluster—^ structure with fibers in a random arrange­ analyzed as derived from a quantitative TEM analysis. ment such that all fibers are intermixed and no single fiber is 5.1.1 This test method docs not describe procedures or isolated from the group; groupings of fibers must have more techniques required to evahistc the safety or habitability of than two points touching. buildings with asbestos-containing materials, or compliance 3.2.4 <febr£r—materials that are of an amount and size with federal, state, or local xeguUtiOQS or statutes. It is the (panicles fcater than 1 mtn in diameter) that can be visually user’s responsibility to make these dnerminatioas. idendfied as to their source. 5.1.2 At present, a single direct relationship between 3.2.S dust—any material composed of r'«< tides in a size isbestos-cooiainiog «haT and potential human exposure dom range of si mm and large enough to settle by vinue of their not exist Accordingly, the user should eOBShterthese data in weight from the ambient air (see definition for settleable relationship to other available infonnation in their evalua­ paniculate matter in Test Method D 1739). tion. 3.2.6 fiber—a structure having a minimum length of 0.5 5.2 This test method uses the defiaition, senleable parti^ pm, an aspect ratio of 3:1 or greater, and substantially Ulate material, found in Test Method D 1739 as the defini­ parallel rides (4). tion of dust This definition accepts all particles small 3.2.7 fibrous—of a mineral composed of parallel, radi­ enough to pass through a 1 mm (No. 18) screen. Thus, a ating, or interlaced aggregates of fibers, from which the fibers single, large asbestos containing particiefs) (from the large are sometimes separable. Thal is, the crystalline aggregate end of the partide size distribution) dispersed during sample may be referred to as fibrous even if it is not composed of preparation may result in anomalously large asbestos con­ separable 'fibers, but has that distinct appearance. The terra centration results in the TEM analyses of that sample. It is. fibrous is used in a general mineralogical way to describe therefore, recommended that multiple indepradent samples are secured from the same area, and a minimum of three aggregates of grains that crystallize in a needlc-Uke habit and samples analyzed by the entire procedure. appear to be composed of fibers. Fibrous has a much more general meaning than asbestos. While it is correct that all 6. loteifetBiices asbestos minerals are fibrous, not all minerals having fibrous 6.1 The following minerals have properties (that is, chem­ habits arc asbestos. ical or crystalline structure) which are very rimily to 3.2.8 indirect preparation—a method in which a sample asbestos minerals and may interfere with the analysis by passes through one or more intermediate steps prior to final causing a false poritive to be recorded during the test. filtration. Therefore, literature references for these materials must be 3.2,9 matrix-^ structure in which one or more fibers, or maintained in the laboratory for comparison to asbestos fiber bundles that are touching, are attached to, or partially minerals so that they are not misidentified as asbestos concealed by a single particle or connected group of non- minerals. fibrous particles. The exposed fiber roust meet the fiber 6.1.1 Antigorite. definition (see 32,6). 6.1 J Palygorskite (Attapulgite). 3X10 Structures—a term that is used to categorize all the 6.1.3 Halloysite. types of asbestos partides udiich are recorded during the 6.1.4 Pyroxenes.. analysis (such as fibers, bundles, dusters, and matrices). 6.1.5 ^ioliU. Hnal results of the test are always expressed in asbestos 6.1.6 yermicullie scrolls. structures per square cennmetre. 6.1.7 Fibrous talc. 6.1.8 Hornblende and other amphiboles other than those listed in 3. IX . 4. Summary of Test Method 6.2 Collecting any dust particles greater than 1 mro in size 4.1 The 'smple is collected by vacuuming a known in this test mctluxl may cause an interference and, therefore, surface area with a standard ZS or 37 mm air sampling must be avoided. cassette using a plastic tube that is attached to the inlet orifice which acts as a nozzle. The sample is transferred from 7. Materials and Equipment . inside the cassette to an aqueous solution of known volume. 7.1 PurUy ofPeagenls—Reageat grade cheroic^ shall be Aliquots of the suspension are then filtered through a used in all tests. Unkss otbirwise indicateri, it is intended membrane. A section of the membrane is prepared and that all reagents con*''' to the spedficazions of the Com- - ' transfetred to a TEM grid using the direct transfer method. niitlec on Analytical Reagents of the Ameriom Chemical K The asbcstiform structures are identified, sized, and counted Society, where such specifications are available. Other grades by TEM, using SAED ano ^DXA at a magnification of may be used, ptovid^ it is first ascertained that the reagent IS pOOio 20OO0X. is of sufTicicnUy high purity to permit its use without

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CITY_21MC100_006537255

NYC-WTC_000209333