ASTM E728-91(1997)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: E 728 – 91 (Reapproved 1997)
Standard Test Method for
Resistance to Attrition of Granular Carriers and
Granular Pesticides
This standard is issued under the fixed designation E 728; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 5. Apparatus
1.1 This test method is used to determine the resistance to 5.1 Brushes, Tyler Model 1778-SB soft brass wire brush, or
attrition of granular carriers and granular pesticides. equivalent, for 100 mesh and coarser sieves. Tyler nylon bristle
1.2 This standard does not purport to address all of the brush, or equivalent, for screens finer than 100 mesh.
safety concerns, if any, associated with its use. It is the 5.2 Mechanical Sieve Shaker, a Tyler Ro-Tap sieveshaker,
responsibility of the user of this standard to establish appro- or equivalent, or other agreed upon device.
priate safety and health practices and determine the applica- 5.3 Sieves, U.S. standard sieves, or equivalent conforming
bility of regulatory limitations prior to use. For specific hazard to Specification E 11. The sieves shall be 2 in. (51 mm) in
statements see Section 6. height and 8 in. (203 mm) in diameter.
5.4 Bottom Receiver Pan and Top Sieve Cover.
2. Referenced Documents
5.5 Steel Balls, ten ⁄8 in. (16 mm) in diameter.
2.1 ASTM Standards: 5.6 Interval Timer, adjustable, with an accuracy of 610 s.
E 11 Specification for Wire-Cloth Sieves for Testing Pur-
5.7 Balance, sensitivity of 0.1 g.
poses 5.8 Beaker, glass, metal, or plastic with 250-mL capacity.
E 725 Test Method of Sampling Granular Carriers and
6. Hazards
Granular Pesticides
6.1 Before testing, read the precautionary statements on the
3. Summary of Test Method
product label, the material safety data sheet, or both. Take
3.1 A known weight of pre-sized granular carrier or granular proper precautions to prevent skin contact and inhalation of the
pesticide is combined with steel balls in a sieve-bottom fines and vapors. Take care to prevent contamination of the
receiver pan. After a specified period of mechanical agitation,
surrounding area. Always wear the appropriate safety equip-
the steel balls are removed and the weight of the granular ment and, where indicated, wear respiratory devices passed by
material passing through the specified limiting sieve is mea-
NIOSH for the product being tested.
sured and the resistance to attrition calculated.
7. Procedure
4. Significance and Use
7.1 For reproducible results on a comparative basis, it is
4.1 This procedure was designed principally with granular necessary to use a narrow mesh fraction or cut for this test.
clay, corncob, nut shell, or sand carriers and granular pesticide
Approximately 75 6 5 g of a representative sample as defined
products, but need not be limited to these materials. There may in Test Method E 725 is required for this test method.
be more appropriate test methods for other types of granular
7.2 Select the limiting screen for the mesh of material to be
carriers and pesticide products. tested. (For 20/40 mesh the limiting screen would be 40, for
18/50 mesh, the limiting screen would be 50, etc.) Preclean
sieves with brush, then wash and dry the sieves.
This test method is under the jurisdiction of ASTM Committee E-35 on
Pesticides and is the direct responsibility of Subcommittee E35.22 on Pesticide
Formulation and Application Systems. The soft brass wire brush (Model No. 1778-SB) a
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