AATCC 24:2004 pdf download.Insects, Resistance of Textiles to
1.1 Biological test methods are given for evaluating the resistance of textiles that contain wool or other susceptible fi- bers to webbing clothes moths and to car- pet beetles. The test methods described here are not concerned with the various procedures for treating textiles [e.g., dye- baths vs. padding application of moth- proofers] or with their subsequent han- dling, ageing, washing, etc. but only with the biological methods to be used to mea- sure the resistance of the [treated or un- treated] textiles to insect attack (see 15.1).
1.2 Two methods are provided for de- termining the extent of damage to test specimens. The Excrement Weight Method is used only for tests with carpet beetles. The Fabric Weight Loss Method is used for tests with webbing clothes moths and also may be used for tests with carpet beetles when preferred and when comparative tests with both insects are made (see Appendix D).
8. Evaluation: Excrement Weight Method
8.1 Insect Survival—Remove and record living and dead insects. Survival counts are made in all cases, since they are important in demonstrating the valid- ity of the test larvae.
8.2 Extent of Damage—Damage to the test specimens is determined by the quan- tity of excrement deposited during the test period as follows:
8.2.1 Remove test specimen from test cage and, by alternately tapping and brushing, transfer all loose material, ex- crement, exuviae, etc., back into the test cage.
8.2.2 Transfer contents of test cage into a No. 3 Gooch crucible and, by repeated tapping of the crucible, the excrement is sifted through the perforations into one of a pair of matched watch glasses.
8.2.3 Weigh the excrement on an ana- lytical balance sensitive to at least 0.2 mg. For the purpose of this test, all mate- rial that sifts through the perforations of the Gooch crucible is construed as excre- ment.
9. Classification: Excrement Weight Method
9.1 The report must include the follow- ing information for each test specimen of the treated sample and the untreated con- trols: (a) Weight of excrement in milligrams. (b) Number of larvae alive.
9.2 The test textile is considered satis- factorily resistant to carpet beetles if an average quantity of excrement of not over 5 mg per specimen is deposited, provided that no single specimen shows more than 6 mg of excrement and that under the same conditions the controls show an av- erage quantity of excrement of not less than 15 mg per specimen.
9.3 The test is invalid if the quantity of excrement deposited on the control speci- mens averages less than 15 mg per speci- men, or if less than 90% of the control larvae survive.AATCC 24 pdf download.