Office of Ground Water and Drinking Water

November 19, 2012

MEMORANDUM

SUBJECT: Basis for Expedited Approval of Methods from ASTM International

FROM: Glynda Smith

Standards and Risk Management Division, Technical Support Center

TO: The Record

This memorandum documents the reviews that were conducted on new versions of methods 

issued by ASTM International. It provides the background information on why EPA is approving these 

methods using the expedited methods approval process. Each method is discussed individually below. 

ASTM Method D 516-11

ASTM Method D 516-07 was approved for the analysis of sulfate in drinking water in the expedited 

methods approval action that was published on November 10, 2009 (74 FR 57908). In the November 

2009 action, ASTM Method D516-07 was compared against the approved version, ASTM Method D 516-

02 which is cited in the drinking water regulations at 40 CFR 143.4(b). Compare the most recent version, 

ASTM D516-11 to the approved version, noting the minor revisions associated with the expedited 

version:

• Section 1.1 defines the lower range of the method as 5 mg/L instead of 1 mg/L. This is the 

same change made in the 2007 expedited version. The sulfate MCL defined at 40 CFR 143.3 is 

250 mg/L; as such, this change in the lower limit has no bearing relative to the MCL.

• Section 1.4 incorporates a statement indicating that SI units (the International System of Units -

abbreviated SI from French: Système International d'unités) are to be regarded as standard.

• In Section 2, all of the separate footnotes citing individual annual books of ASTM Standards 

have been consolidated into a single footnote citing the ASTM website (www.astm.org).

• In Section 2, one of the referenced documents has been eliminated (ASTM D1192 –

Specification for Equipment for Sampling Water and Steam in Closed Conduits). This reference 

is not necessary since a separate reference (ASTM D3370) also describes sampling water from 

closed conduits.

• Section 8.5 was modified to allow the use of commercially prepared stock standard sulfate 

solutions. This change was also noted in the 2007 version that was expedited.

• Section 10.1 no longer lists a 2.0 mg/L standard for the calibration curve. This same change 

was noted in the 2007 version that was expedited. Even without this standard, the calibration 

curve still incorporates seven standards, which is more than sufficient for a linear curve. 

• Section 11.1 specifies the type of filter (0.45 μm membrane) to use with turbid samples. This 

same change was noted in the 2007 version that was expedited.

• Note 4 has been added which states that if dilution does not address interferences effectively, 

the analyst should use a different method.

The methods are otherwise identical with respect to sample collection and handling protocols, sample 

preparation, analytical procedure and calculation of sulfate concentration in the sample. The precision 
and bias are unchanged. Therefore, ASTM D 516-11 is equally as effective as the approved method 

ASTM D516-02, for determining sulfate concentration in drinking water.

ASTM Method D 1067-11 B

ASTM Method D 1067-06 B was approved for the determination of alkalinity in drinking water in the 

expedited methods approval action that was published on June 24, 2011 (76 FR 37014). In the June 

2011 action, ASTM Method D 1067-06 B was compared against the approved version, ASTM Method D 

1067-02 B which is cited in the drinking water regulations at 40 CFR 141.23(k)(1). Compare the most 

recent version, ASTM D1067-11 B to the approved version, noting the minor revisions associated with 

the expedited version:

• Added new Section 1.6 which incorporates a statement indicating that SI units (the International 

System of Units – abbreviated SI from French: Système International d'unités) are to be 

regarded as standard.

• In Section 2, all of the separate footnotes citing individual annual ASTM Standards books have 

been consolidated into a single footnote citing the ASTM website (www.astm.org).

• In Section 20 (Reagents), Note 5 has been added to indicate that indicators are also 

commercially available in prepared form.

• Reworded the QC subsection 34.1.2.3.

The methods are otherwise identical with respect to sample collection and handling protocols, sample 

preparation, and analytical procedure for determination of alkalinity in the sample. The precision and 

bias are unchanged. Therefore, ASTM D 1067-11 B is equally as effective as the approved method ASTM 

D1067-02 B, for determining alkalinity in drinking water.

ASTM Method D 1293-12

ASTM Method D1293-12 for the analysis of pH in drinking water was compared against the approved 

version, ASTM Method D 1293-99 which is cited in the drinking water regulations at 40 CFR 141.23(k)(1). 

The following changes have been made in ASTM Method D 1293-12 relative to the approved version:

• Section 1.3 cites ASTM Method D6569 for more detail regarding on-line pH measurement. This 

method is not approved for use in measuring pH, but cited only as a reference is not a problem.

• Section 1.7 incorporates a statement indicating that SI units (the International System of Units –

abbreviated SI from French: Système International d'unités) are to be regarded as standard.

• Added the following to the definition of pH: pH is the “negative logarithm of the hydrogen ion 

activity in an aqueous solution or the logarithm of the reciprocal of the hydrogen ion activity.”

• Added the following statement to Section 10.4: “The thermocompensator may be incorporated 

into the pH electrode or may be a separate probe.”

• Added the following text to Section 11.1 regarding Reference Buffer Solutions: “If traceability to 

NIST standard reference materials (SRMs) is required, follow exactly the NIST certificate drying, 

preparation, and storage instructions for the given renewal of the respective SRM buffer, and 

obtain the certified value from the certificate for that SRM renewal at the applicable 

temperature. Buffer solution compositions and preparations given in Sections 11.1.1 through 

11.1.7 are for use with non-NIST materials. For NIST SRMs, follow the instructions included with 

the SRM.”

• Modified Table 3 to incorporate recommended drying procedures for non-NIST reference buffer 

materials.

• Added the following text to Sect. 11.1.1: “When using the NIST SRM, prepare in accordance 

with the current renewal certificate. For other reference materials, follow associated 
instructions or...” (remaining text in section is unchanged). This same text also prefaces Sections 

11.1.2 through 11.1.7.

• Section 12.5 added the following text after discussion of calibrating with the first reference 

buffer: “Alternatively, follow the manufacturer’s instructions for calibration with the first 

buffer.”

• Added new Section 12.7: “Use additional portions of the second reference buffer solution, as 

before, until two successive readings differ by not more than + 0.02 pH units from the pHs. 

Alternatively, follow the manufacturer’s instructions for calibration with the second buffer.”

• Added new Section 12.8: “Interim Checks: The assembly shall be judged to be operating 

satisfactorily if the reading obtained for the second reference buffer solution agrees with its 

assigned pHs value within + 0.05 (or less) pH units.”

• Section 13.2 adds the option of using a pH electrode with integral temperature sensor.

• Added text in Section 19 discusses the use of direct pipe mounting for process pH measurement 

equipment.

• Added text to standardization Sect. 21 to follow the manufacturer’s instructions for calibration 

(if procedural steps differ from those suggested in the method).

• Section 22 expands temperature measurement options beyond the use of a thermometer to 

include the use of ATC probes and pH electrodes with integral temperature sensors.

The methods are otherwise identical with respect to sample collection and handling protocols, 

sample preparation, analytical procedure and calculation of uranium concentration in the sample. 

The precision and bias are unchanged. Therefore, ASTM D 1293-12 is equally as effective as the 

approved method ASTM D1293-99, for determining pH in drinking water.