ASTM D1172-95

Standard Guide for pH of Aqueous Solutions of Soaps and Detergents

SCOPE
1.1 This guide covers the preparation of aqueous solutions of soaps and detergents and the determination of their pH.
1.2 The values stated in SI units are to be regarded as the standard.
1.3 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. Material Safety Data Sheets are available for reagents and materials. Review them for hazards prior to usage.

General Information

• Status: Historical
• Publication Date: 14-Apr-1995
• Technical Committee: D12 - Soaps and Other Detergents
• Drafting Committee: D12.15 - Physical Testing

Relations

• Replaced By: ASTM D1172-95(2001) - Standard Guide for pH of Aqueous Solutions of Soaps and Detergents
• Effective Date: 15-Apr-1995
• Referred By: ASTM D4252-89(2017) - Standard Test Methods for Chemical Analysis of Alcohol Ethoxylates and Alkylphenol Ethoxylates
• Effective Date: 15-Apr-1995
• Referred By: ASTM D8179-18 - Standard Guide for Characterizing Detergents for the Cleaning of Clinically-used Medical Devices
• Effective Date: 15-Apr-1995
• Referred By: ASTM D1570-95(2023) - Standard Test Methods for Sampling and Chemical Analysis of Fatty Alkyl Sulfates
• Effective Date: 15-Apr-1995
• Referred By: ASTM D3673-89(2016) - Standard Test Methods for Chemical Analysis of Alpha Olefin Sulfonates
• Effective Date: 15-Apr-1995

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 1172 – 95
Standard Guide for
pH of Aqueous Solutions of Soaps and Detergents
This standard is issued under the fixed designation D 1172; 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 volumetric flask. Partially fill the flask with distilled water or
equivalent and agitate until the sample is completely dissolved.
1.1 This guide covers the preparation of aqueous solutions
Make certain the solute is completely dissolved and allow time
of soaps and detergents and the determination of their pH.
for the evolution of dissolved gases. Fill to the calibration mark
1.2 The values stated in SI units are to be regarded as the
with distilled water or equivalent. Stopper the flask; mix
standard.
thoroughly. The desirable condition requires the solution to
1.3 This standard does not purport to address all of the
come to equilibrium. Allow the solution to equilibrate at 25 6
safety concerns, if any, associated with its use. It is the
2.0°C. The use of a temperature compensation probe may
responsibility of the user of this standard to establish appro-
allow alternate temperatures. Records should show the time
priate safety and health practices and determine the applica-
interval between solution preparation and pH measurement.
bility of regulatory limitations prior to use. Material Safety
Data Sheets are available for reagents and materials. Review
NOTE 1—The procedure for detergents other than soaps is applicable to
them for hazards prior to usage.
some compositions that contain minor proportions of soap, provided that
the solutions do not show evidence of gelling prior to carrying out the pH
2. Referenced Documents
measurement.
NOTE 2—Measurements of pH of gelled solutions lack constancy and
2.1 ASTM Standards:
reproducibility. The procedure for soaps (Section 6) is designed to produce
D 460 Test Methods for Sampling and Chemical Analysis
solutions that will not gel before the pH measurement is carried out. This
of Soaps and Soap Products
procedure should be used for all detergent solutions, soap or nonsoap, that
D 501 Test Methods of Sampling and Chemical Analysis of
give evidence of gelling or incomplete solution when prepared in
Alkaline Detergents
accordance with 5.1. The procedure for soaps is not applicable to detergent
compositions that are known to be chemically altered by the boiling water
E 70 Test Method for pH of Aqueous Solutions with the
used in dissolving the sample, or that are intended exclusively for use in
Glass Electrode
cold water.
3. Sampling
5.2 Determination of pH—Calibrate the pH meter and
3.1 The material shall be sampled in accordance with Test suitable electrodes. The recommended electrodes are Fischer
Methods D 460 or D 501, whichever is applicable. Accuphast combination electrode or Orion Ross Sure Flow
electrode or equivalent electrodes. Measure the pH of the
4. Reagent
solution while stirring.
4.1 Distilled Water or Equivalent—Distilled water or
6. Procedure for Soaps
equivalent shall be boiled thoroughly, or purged with CO -free
air, to remove CO and shall be protected with so
...