ASTM D4576-16

Standard Test Method for Mold Growth Resistance of Wet Blue and Wet White

SIGNIFICANCE AND USE
4.1 This test method provides a technique for evaluating mold growth resistance characteristics of Wet Blue and Wet White, and should assist in the prediction of storage time before molding occurs.  
4.2 The degree of correlation between this test and commercial quantities of Wet Blue and Wet White in storage or shipment situations, or both, has not been fully determined.
SCOPE
1.1 This test method covers the determination of mold growth resistance of Wet Blue and Wet White subject to storage and shipping requirements and intended for use in leather manufacturing. This test method may not be suitable to evaluate fungicides that are inactivated by proteins. This includes alkyldimethylbenzyl ammonium chlorides.  
1.2 Conclusions about mold growth resistance are drawn from the results by comparing the test with a simultaneously run control of known resistance. Success or failure is determined by the amount of mold growth relative to the control.  
1.3 To allow use of this test method by any laboratory, flexibility has been permitted in times, temperature, and humidity of incubation, inoculum, hide sampling area, and choice of control. These may be adjusted to fit local conditions but must be standardized.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-May-2016
• ICS: 59.140.30 - Leather and furs
• Technical Committee: D31 - Leather
• Drafting Committee: D31.02 - Wet Blue

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4576 − 16
Standard Test Method for
1
Mold Growth Resistance of Wet Blue and Wet White
This standard is issued under the fixed designation D4576; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2 After various incubation periods, mold growth is rated
asapercentageoftheWetBlueandWetWhitesurfacecovered
1.1 This test method covers the determination of mold
by mold.
growthresistanceofWetBlueandWetWhitesubjecttostorage
and shipping requirements and intended for use in leather 3.3 ResistancetomoldgrowthoftheWetBlueorWetWhite
manufacturing. This test method may not be suitable to
test specimen is determined by comparison with Wet Blue or
evaluate fungicides that are inactivated by proteins. This Wet White of known resistance characteristics (the control),
includes alkyldimethylbenzyl ammonium chlorides.
that is tested simultaneously.
1.2 Conclusions about mold growth resistance are drawn
4. Significance and Use
from the results by comparing the test with a simultaneously
4.1 This test method provides a technique for evaluating
run control of known resistance. Success or failure is deter-
mold growth resistance characteristics of Wet Blue and Wet
mined by the amount of mold growth relative to the control.
White, and should assist in the prediction of storage time
1.3 To allow use of this test method by any laboratory,
before molding occurs.
flexibility has been permitted in times, temperature, and
4.2 Thedegreeofcorrelationbetweenthistestandcommer-
humidity of incubation, inoculum, hide sampling area, and
cial quantities of Wet Blue and Wet White in storage or
choiceofcontrol.Thesemaybeadjustedtofitlocalconditions
shipment situations, or both, has not been fully determined.
but must be standardized.
1.4 The values stated in SI units are to be regarded as
5. Interferences
standard. No other units of measurement are included in this
5.1 Acommon interference is contamination of plates, agar,
standard.
or samples by unwanted organisms that settle in from the
1.5 This standard does not purport to address all of the
environment.
safety concerns, if any, associated with its use. It is the
5.2 Volatility and Leachability of Biocides—A “zone of
responsibility of the user of this standard to establish appro-
inhibition” where no mold grows on the agar adjacent to the
priate safety and health practices and determine the applica-
specimen indicates that the fungicide may leach.
bility of regulatory limitations prior to use.
6. Apparatus
2. Terminology
6.1 Petri Dishes, 120 mm diameter. Sterile plastic dispos-
2.1 Definitions of Terms Specific to This Standard:
able dishes are preferred.
2.1.1 Wet Blue—hide or skin, or split of a hide or skin,
6.2 Incubator, or location providing similar conditions be-
tanned with basic chromium sulfate, containing approximately
ing free of drafts, and capable of a constant (6 2°C) tempera-
50% moisture and having an acidic pH.
ture within the 26 to 30°C range.
2.1.2 Wet White—a hide or skin, or split of a hide or skin
tanned with organic or non-organic tanning agents (excluding 6.3 Medicine droppers,disposableplastictypedelivering30
chromium or iron containing agents and vegetable extracts),
to 35 drops per mL.
containing approximately 50 % moisture.
7. Reagents and Materials
3. Summary of Test Method
2
7.1 Potato Dextrose Agar, a dehydrated plating medium
3.1 Wet Blue and Wet White test specimens are surrounded
used in culturing yeasts and molds from dairy products.
by but not covered with agar, inoculated, and incubated.
2
The sole source of supply of a product that meets the requirements of this
1
ThistestmethodisunderthejurisdictionofASTMCommitteeD31onLeather method known to the committee at this time is Potato Dextrose Agar stock no.
and is the direct responsibility of Subcommittee D31.02 on Wet Blue. 0013-01-4, available from Difco Labs, P.O. Box 1058A, Detroit, MI28232. If you
Current edition approved June 1, 2016. Published June 2016. Originally are aware of alternative suppliers, please provide this information to ASTM
approved in 1986. Last previous edition approved in 2013 as D4576-08(2013). International Headquarters. Your comments will receive careful consideration at a
1
DOI: 10.1520/D4576-16. meeting of the responsible technical committee, which you may attend.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4576 − 16
3 6 5
7.2 Inoculum, Aspergillus niger 1×10 spores per mL, or 9.3.2 Use three drops of 1×10 spores per millilite
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D4576 − 08 (Reapproved 2013) D4576 − 16
Standard Test Method for
1
Mold Growth Resistance of Wet Blue and Wet White
This standard is issued under the fixed designation D4576; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the determination of mold growth resistance of wet blue and wet whiteWet Blue and Wet White
subject to storage and shipping requirements and intended for use in leather manufacturing. This test method may not be suitable
to evaluate fungicides that are inactivated by proteins. This includes alkyldimethylbenzyl ammonium chlorides.
1.2 Conclusions about mold growth resistance are drawn from the results by comparing the test with a simultaneously run
control of known resistance. Success or failure is determined by the amount of mold growth relative to the control.
1.3 To allow use of this test method by any laboratory, flexibility has been permitted in times, temperature, and humidity of
incubation, inoculum, hide sampling area, and choice of control. These may be adjusted to fit local conditions but must be
standardized.
1.4 For mold growth resistance of wet white, the procedure is identical, substitute wet white for wet blue in the standard method.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Terminology
2.1 Definitions of Terms Specific to This Standard:
2.1.1 wet blue—Wet Blue—hide or skin, or split of a hide or skin, tanned with basic chromium sulfate, containing approximately
50 % moisture and having an acidic pH.
2.1.2 wet white—Wet White—a hide or skin, or split of a hide or skin tanned with organic or non-organic tanning agents
(excluding chromium or iron containing agents and vegetable extracts), containing approximately 50 % moisture.
3. Summary of Test Method
3.1 Wet blue Blue and Wet White test specimens are surrounded by but not covered with agar, inoculated, and incubated.
3.2 After various incubation periods, mold growth is rated as a percentage of the wet blue Wet Blue and Wet White surface
covered by mold.
3.3 Resistance to mold growth of the wet blue Wet Blue or Wet White test specimen is determined by comparison with wet blue
Wet Blue or Wet White of known resistance characteristics (the control), that is tested simultaneously.
4. Significance and Use
4.1 This test method provides a technique for evaluating mold growth resistance characteristics of wet blue, and Wet Blue and
Wet White, and should assist in the prediction of storage time before molding occurs.
4.2 The degree of correlation between this test and commercial quantities of wet blue Wet Blue and Wet White in storage or
shipment situations, or both, has not been fully determined.
5. Interferences
5.1 A common interference is contamination of plates, agar, or samples by unwanted organisms that settle in from the
environment.
1
This test method is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcommittee D31.02 on Wet Blue.
Current edition approved May 1, 2013June 1, 2016. Published May 2013June 2016. Originally approved in 1986. Last previous edition approved in 20082013 as
D4576 - 08.D4576 - 08(2013). DOI: 10.1520/D4576-08R13.10.1520/D4576-16.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4576 − 16
5.2 Volatility and Leachability of Biocides—A “zone of inhibition” where no mold grows on the agar adjacent to the specimen
indicates that the fungicide may leach.
6. Apparatus
6.1 Petri Dishes, 120 mm diameter. Sterile plastic disposable dishes are preferred.
6.2 Incubator, or location providing similar conditions being free of drafts, and capable of a constant (6 2°C) temperature
within the 26 to 30°C range.
6.3 Medicine droppers, disposable plastic type delivering 30 to 35 drops per mL.
7. Reagents and Materials
2
7.1 Potato Dextrose Agar, a dehydrat
...