Equivalency Assessment 

Revisions to Currently Approved 

ASTM Drinking Water Methods 

in 40 CFR 141.25 

for 

Expedited EPA Method Approval Action

 FINAL (01/21/2010)

 

Prepared by: 

Larry Umbaugh 

Environmental Scientist Leader - Senior Radiochemist 

Computer Sciences Corporation (CSC) 

6101 Stevenson Avenue 

Alexandria, VA 22304 

Prepared in Support of 

EPA Work Assignment 4-21 under EPA Contract No. EP-C-05-045 
2

1.0 Activity Description 

CSC was directed, on 12/7/09, to review six updated ASTM methods and provide recommendations 

as to whether they are suitable for approval in an Expedited Method Approval action. The review 

was conducted as a comparison of the updated versions to the versions that are cited in 40 CFR 

141.25(a). The review evaluated any changes in the methods that may impact the performance of 

the method. 

 

2.0 Evaluation Conclusions 

Details of the evaluation of revisions to the six ASTM methods are provided in the attached memo. 

It was determined that the revisions, in all six methods, did not change sample handling or the 

analytical chemistry process. It is recommended that Environmental Protection Agency (EPA) 

considers the new versions of the ASTM standards to be “equally effective” as the approved ASTM 

methods cited in 40 CFR 141.25(a). The following table lists the currently approved ASTM 

methods under the Safe Drinking Water Act (SDWA) and the corresponding method revisions that 

were reviewed for approval.

Currently Approved 

(40 CFR 141.25) 

ASTM Method 

Approved Method Title ASTM 

Method 

Revision 

Revised 

Method Title 

Recommended 

for Approval? 

D 2460-97 Standard Test Method for 

Alpha-Particle-Emitting 

Isotopes of Radium in 

Water 

D 2460-07 Standard Test Method for 

Alpha-Particle-Emitting 

Isotopes of Radium in 

Water 

Yes 

D 3454-97 Standard Test Method for 

Radium-226 in Water 

D 3454-05 Standard Test Method for 

Radium-226 in Water 

Yes 

D 3649-98a Standard Practice for 

High-Resolution GammaRay Spectrometry in 

Water 

D 3649-06 Standard Practice for 

High-Resolution GammaRay Spectrometry in 

Water 

Yes 

D 4107-98 

(Reapproved 2002) 

Standard Test Method for 

Tritium in Drinking Water 

D 4107-08 Standard Test Method for 

Tritium in Drinking Water 

Yes 

D 4785-00a Standard Test Method for 

Low-Level Iodine-131 in 

Water 

D 4785-08 Standard Test Method for 

Low-Level Analysis of 

Iodine Radioisotopes in 

Water 

Yes 

D 5147-02 Standard Test Method for 

Trace Uranium in Water 

by Pulsed-Laser 

Phosphorimetry 

D 5174-07 Standard Test Method for 

Trace Uranium in Water 

by Pulsed-Laser 

Phosphorimetry 

Yes 
3

Office of Ground Water and Drinking Water 

January 4, 2010 

MEMORANDUM

 

SUBJECT: Basis for Expedited Approval of Methods from ASTM International 

FROM: Michella Karapondo, Chemist 

 

 

TO: The Record 

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

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

approving these methods using the expedited method approval process. Each method is 

discussed individually below: 

1) ASTM International Method D 2460-07:

Method D 2460-97 was used as the basis for comparison, because it is currently promulgated in 

the drinking water regulations at 40 CFR 141.25(a) for determining alpha particle-emitting 

isotopes of radium in water. The following changes are included in the newer version: 

 Section 2.1 was modified to update referenced ASTM standards; Standards D 

4448, D 5847, and D 6001 were added. 

 Section 6, concerning interferences, was modified to add additional discussions 

on: 

- Interferences from the presence of suspended solids or insoluble precipitates 

that will bias the chemical yield high and lead to falsely low sample results 

(Section 6.2). 

- Radium progeny in-growth and decay that will interfere with the total alpha 

particle emission rate over time (Section 6.3). 

- Precipitate mass that will interfere with alpha particle detection efficiency 

(Section 6.4). 

- Self-absorption interference effects that may be addressed during the 

calibration process (Section 6.5). 

 Section 8.6 was modified to add the molarity of the ammonium hydroxide. 

 Section 8.7 was modified to add standardization instructions (Section 8.7.1) for 

the barium nitrate carrier solution. 

 Section 8.13 was modified to add the molarity of the sulfuric acid. 

 Section 10.1 was modified to add additional ASTM reference Standards D 4448 

and D 6001 for the collection of non-drinking water samples. 

 Section 11 was modified by splitting Section 11.1 into 3 separate sections; the text 

remains the same. 
4

 Section 13.2 was modified to change the following concentration calculation 

terms; the calculation remains the same: 

- D was changed to, AC226Ra = concentration of Ra-226, Bq/L 

- C = net count rate was changed to Rn 

- F was changed to, IF = correction for the ingrowth of descendants between 

the time of separation and the time of counting. 

 Table 1 was updated to expand the correction factor range for in-growth of alpha 

activity into initially pure radium-226, from 72 hours to 720 hours. 

 Figure 1 was updated to expand the range of the in-growth and decay curves from 

the time of separation, to 30 days versus 7 days in D 2460-97. 

 Figure 2 was added to provide information on the typical alpha particle efficiency 

as a function of time and precipitate mass. 

 Section 13.4 was modified to update the terminology for the calculation of the 

analysis uncertainty from the older, total propagated uncertainty (TPU), in D 

2460-97, to the currently used combined standard uncertainty (CSU). This update 

is consistent with the U.S. Nuclear Regulatory Commission, Multi-Agency 

Radiological Laboratory Analytical Protocols Manual, NUREG-1576 EPA 402-

B-04-001A, July 2004, (MARLAP). 

 Section 13.4.1 was modified to change the following one-sigma uncertainty 

calculation terms; the calculation remains the same: 

- G was changed to Rs

- B was changed to Rb

- tG was changed to ts

 Section 13.5 was modified to update the calculation of the a priori minimum 

detectable concentration (MDC) to be consistent with MARLAP. 

 Section 15 has been rewritten to include detailed instructions: 

- Section 15.1 defines the quality control (QC) program for the instrument and 

details the size of an analytical batch to be limited to 20 samples. 

- Section 15.2 details detector efficiency calibration verification. 

- Section 15.3 describes the steps necessary for initial demonstration of the 

laboratory/instrument/analyst capability. 

- Section 15.4 details laboratory control sample requirements in analytical 

batches. 

- Section 15.5 provides for method blank requirements in an analytical batch. 

- Section 15.6 describes the requirements for analytical batch matrix spikes. 

- Section 15.7 presents the requirements for duplicates in the batch analysis. It 

also delineates the duplicate error ratio calculation and acceptance criteria. 

- Section 15.8 defines the requirements for quarterly verification of the 

quantitative value produced by the test method by analyzing independent 

reference material that has been submitted on at least a single-blind basis. 

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of 

radium-226 concentrations has been updated to capture the uncertainty determinations 

outlined in MARLAP; precision and bias are unchanged. The QC requirements in D 

2460-07 are far more detailed compared to those cited in D 2460-97. Therefore, Method 
5

D 2460-07 is considered to be equally as effective as D 2460-97 for determining radium226 concentrations in drinking water. 

2) ASTM International Method D 3454-05: 

Method D 3454-97 was used as the basis for comparison, because it is currently promulgated in 

the drinking water regulations at 40 CFR 141.25(a) for determining radium-226 in water. The 

following changes are included in the newer version: 

 Section 2.1 was modified to update referenced ASTM standards; Standard D 5847 

was added. 

 Section 7.5 was modified, for the determination of acceptable background 

counting rate, from 0.00 to 0.03 counts per minute (cpm) to 0.00 to 0.0005 counts 

per second (cps). 

 Sections 8.13 and 8.14 were updated to include the molarity of the hydrochloric 

acid solution. 

 Section 8.16 was updated to include the weight percent of the hydrogen peroxide. 

 Section 8.19 was modified to update known suppliers. 

 Section 8.20 was modified to update known suppliers. 

 Section 8.22 was updated to include the molarity of the sulfuric acid solution. 

 Section 10.16 was modified to change the following term in the calculation for the 

cell calibration constant: 

C = net count rate was changed to Rn; the calculation remains the same. 

 Section 10.17 was expanded to provide additional calibration frequency 

requirements. 

 Section 11.1.14 was modified to change the sample yield term from Y to RY. 

 Section 11.12.10 was revised to eliminate repeated verbiage from Section 11.12.9. 

 Section 12.1 was modified to change the following concentration calculation 

terms; the calculation remains the same: 

- D was changed to, AC226Ra = concentration of Ra-226, Bq/L 

- Rn was previously changed in Section 10.16 

- RY was previously changed in Section 11.1.14 

- V was changed to Va = volume of sample used, L 

 Section 12.2 was modified to update the terminology for the calculation of the 

analysis uncertainty from the older, total propagated uncertainty (TPU), in D 

3454-97, to the currently used combined standard uncertainty (CSU). This update 

is consistent with MARLAP. 

 Section 14 has been rewritten as noted below: 

- Section 14.2 details calibration and calibration verification steps. 

- Section 14.3 details detector efficiency verification. 

- Section 14.4 describes the steps necessary for initial demonstration of the 

laboratory and instrument capabilities. 
6

- Section 14.5 details laboratory control sample requirements for analytical 

batches. 

- Section 14.6 provides for method blank requirements in an analytical batch. 

- Section 14.7 describes the requirements for analytical batch matrix spikes. 

- Section 14.8 presents the requirements for duplicates in the batch analysis. It 

also delineates the duplicate error ratio calculation and acceptance criteria. 

- Section 14.9 defines the requirements for quarterly verification of the 

quantitative value produced by the test method by analyzing independent 

reference material that has been submitted on at least a single-blind basis. 

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of 

radium-226 concentration has been updated to capture the uncertainty determinations 

outlined in MARLAP. The precision and bias are unchanged. The QC requirements in D 

3454-05 are far more detailed than those cited in D 3454-97. Therefore, Method D 3454-

05 is considered to be equally as effective as D 3454-97 for determining radium-226 

concentrations in drinking water.

3) ASTM International Method D 3649-06:

Method D 3946-98a was used as the basis for comparison, because it is currently promulgated in 

the drinking water regulations at 40 CFR 141.25(a) for determining gamma emitters in water. 

The following changes are included in the newer version:

 Section 1.1 was modified to change the applicability of the procedure to nuclides 

emitting gamma-rays with energies greater than 45 keV versus those with 

energies greater than 20 keV as stipulated in D 3946-98a. The increase of the 

lower end energy is more appropriate to match typical low energy calibration 

standards. New technology (digital signal processors) was also included to 

accommodate high count rate samples. 

 Section 1.2 was modified to allow for relative determinations of samples other 

than just tracers. References have also been updated in this section. 

 Section 2.1 was modified to update referenced ASTM standards; the discontinued 

ASTM Standard D 3085 was deleted, and Standard D 4488 was added. 

 Section 4.1 was expanded to include all the components in the gamma ray 

spectrometer signal chain. 

 Section 4.2 was modified to remove antiquated lithium-drifted germanium, 

Ge(Li), detectors. New technology (electromechanical cooling) was added as an 

alternative to liquid nitrogen cooling. 

 Section 4.4 was modified, because of newer computer technology, to expand the 

system memory from 2000 channels to 4000 channels to fully utilize a germanium 

detector’s energy resolution. 

 Section 4.6 was modified to remove cathode-ray tube (CRT). 

 Section 4.7 was modified to remove 1 keV per channel, which is appropriate only 

if 2000 channels are used (see Section 4.4). 
7

 Section 5.3 was modified to lower the distance for high activity samples from the 

detector to 10 centimeters instead of 1 meter. 

 Section 5.4 was modified to simplify the gross count rate determination from 

100,000 counts per minute to 2,000 counts per second, to eliminate electronic 

problems,. 

 Section 6.1 was modified to remove reference to a method of predicting the 

gamma-ray resolution of a detector. 

 Section 6.3 was modified to increase the acceptable counting rate from 1,000 

counts per second to 2,000 counts per second, to minimize random summing. 

 Section 6.4 was added to the method to discuss sample density as being a factor 

that can affect quantitative results. 

 Section 7 apparatus was updated to reflect current technology upgrades in gamma 

ray spectrometer system components. 

 Section 8.1 was revised to include the following updates: D 1066 Practice for 

Sampling Steam and D 4448 Guide for Sampling Ground-Water Monitoring 

Wells for additional sample collection criteria. 

 Section 10.1 was modified to raise the calibration source activity to a range of 1 to 

1000 k Becquerel (Bq), to reflect better electronics in current gamma ray 

spectrometry systems. 

 Section 10.2.1.2 was modified to add a statement on cascade and random 

summing interferences that should be considered during calibration. 

 Section 10.3.1 was modified to include a new Table 1 that lists some 

commercially available nuclides suitable for energy calibrations. 

 Section 10.3.1.1 was revised to delete the following sentence: “The radionuclide 

purity of the standards should be verified periodically to ensure against accidental 

contamination or the presence of long-lived impurities by comparing the observed 

spectra published in the literature (8).” The deletion of this sentence is 

appropriate because routine QC checks, using the calibration standards, will 

verify potential contamination and/or impurity issues. 

 Section 10.3.2 has been modified, for the verification of the energy calibration, 

from “During each day in which the spectrometry system is being used to analyze 

samples, the above sequence of operation shall be repeated using at least two 

different gamma-ray energies” to “The energy calibration should be verified at a 

predetermined interval.” The daily or before-use requirement has been moved to 

Section 14.2. 

 Efficiency calibration equation terms included in Section 10.4.2 have been 

modified to those below; the calculations are the same: 





R

Rnet

f 

Where: 

εf = full-energy peak efficiency (counts per gamma-ray emitted), 

Rnet = net gamma-ray count in the full-energy peak of interest (counts per 

second), and 
8

Rγ = gamma-ray emission rate (gamma rays per second). If the standard 

source is calibrated as to activity, the gamma-ray emission rate is given 

by: 

 Rγ = A × I

Where: 

A = activity in becquerels (Bq), and 

I = absolute gamma intensity for the specific gamma-ray emission. 

 Section 12.4 has been modified to remove the nuclear decay data table and the 

user is referred to References 6, 7, and 8 for such data. 

 Section 12.5 has been revised to modify the calculation terms to those below; the 

calculation is the same: 

  V I DF

R AC net

    

Where: 

Rnet = net count rate (s-1), 

V = test specimen volume (L), 

ε = detector efficiency factor, 

I = absolute gamma intensity, and 

DF = radionuclide decay correction factor (correction for radioactive decay). 

 Section 12.6 was added to update the terminology for calculation of the analysis 

uncertainty from the older total propagated uncertainty (TPU, in D 3649-98a), to 

the currently used combined standard uncertainty (CSU). This update is 

consistent with MARLAP. 

 Section 12.7 was added to provide clarification for calculation of the net count rate 

(Rnet) and the counting uncertainty [u(Rnet)].

 Section 12.9 was added to reference ASTM D 3648, Standards for the 

Measurement of Radioactivity, for detailed discussion on minimum detectable 

concentration concepts. 

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of 

gamma-ray emitting nuclide concentrations has been updated to capture the uncertainty 

determinations outlined in MARLAP. The precision and bias are unchanged. Therefore, 

Method D 3649-06 is considered to be equally as effective as D 3649-98a for determining 

gamma-ray emitting nuclide concentrations in drinking water. 
9

4) ASTM International Method D 4107-08: 

Method D 4107-98 (Reapproved 2002) was used as the basis for comparison, because it is 

currently promulgated in the drinking water regulations at 40 CFR 141.25(a) for determining 

tritium in water. The following changes are included in the newer version: 

 Section 2.1 was modified to update referenced ASTM standards. 

 Section 8.6 was added to include the NIST traceable tritium standard as a reagent 

and material. 

 Section 10.1.1 was modified to define that 17 disintegrations/second are equal to 

17 Becquerel. The acronym RWTS was added for raw water tritium standard. 

 Section 10.1.1 was modified by moving the last sentence in Section 10.1.1 to the 

first sentence in 10.1.1.1. The acronym DWTS was added for distilled water 

tritium standard. 

 Section 10.1.2 was modified to add the acronym DRWTS for distilled raw water 

tritium standard. 

 Section 11.1 was modified by taking the last 2 sentences in the Note and making 

them Section 11.2. The remaining sections (11.3 through 11.5) were then 

incremented by one number, ending at Section 11.16. 

 Section 12.1 was modified to update the calculation for detection efficiency to 

reflect the previously defined acronyms. The detection efficiency calculation was 

updated to add the standard uncertainty for the activity of the DWTS. This update 

is consistent with MARLAP. 

 Section 12.2 was updated to reflect the previously defined acronyms for the 

recovery correction factor calculation. 

 Section 12.3 was updated to include the half-life correction in the tritium activity 

calculation. 

 Section 12.3.1 was replaced with Section 12.4. The update includes the 

calculation of the combined standard uncertainty (CSU) of the tritium 

concentration in the sample due to counting statistics. This update is consistent 

with MARLAP. 

 Section 12.4 was replaced with Section 12.5 which updates the terminology for 

calculation of the analysis uncertainty from the older, total propagated uncertainty 

(TPU, in D 4707-98), to the currently used combined standard uncertainty (CSU). 

This update is consistent with MARLAP. 

 Section 12.6 was added to calculate the critical activity concentration Lc. This 

update is consistent with MARLAP.

 Section 12.7 was added to provide the calculation of the a priori minimum 

detectable activity concentration (MDC). This addition is consistent with 

MARLAP.

 Section 13 has been rewritten as noted below: 

- Section 13.2 describes the steps necessary for initial demonstration of 

laboratory and instrument quality. 

- Section 13.3 details laboratory control sample requirements in analytical 

batches. 

- Section 13.4 provides for method blank requirements in an analytical batch. 
10

- Section 13.5 describes the requirements for analytical batch matrix spikes. 

- Section 13.6 presents the requirements for duplicates in the batch analysis. It 

also delineates the duplicate error ratio calculation and acceptance criteria. 

- Section 13.7 defines the requirements for quarterly verification of the 

quantitative value produced by the test method by analyzing independent 

reference material that has been submitted on at least a single-blind basis. 

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of tritium 

concentration has been updated to capture the uncertainty determinations outlined in MARLAP. 

The QC requirements in D 4107-08 are far more detailed than those cited in D 4107-98. 

Therefore, Method D 4107-08 is considered to be equally as effective as D 4107-98 for 

determining tritium concentrations in drinking water. 

5) ASTM International Method D 4785-08:

Method D 4785-00a was used as the basis for comparison, because it is currently promulgated in 

the drinking water regulations at 40 CFR 141.25(a) for determining radioactive iodine in water. 

The following changes are included in the newer version: 

 The method title was changed to Standard Test Method for Low-Level Analysis of 

Iodine Radioisotopes in Water. 

 Section 1.1 was modified to remove specificity for iodine-131(131I) and replace it 

with radioactive iodine in water. 

 Section 2.1 was modified to update referenced ASTM standards; Standard D 5847 

was added. 

 Section 5.1 was modified to add the capability of analyzing additional isotopes of 

iodine (in addition to 131I). However, it also states that other iodine isotopes have 

not been tested according to ASTM Standard D 2777 and that the user must 

determine the precision and bias for radioactive isotopes of iodine other than 131I. 

 Section 5.2 was added to address the method’s applicability to analysis of iodine 

radioisotopes with half-lives greater than 2 hours, which include 121I, 123I, 124I, 

125I, 126I, 129I, 130I, 131I, 132I, 133I, and 135I. 

 Section 6.2 was added to inform the user that, due to X-ray interferences at and 

below 33.6 keV, only discreet gamma energy lines at and above 35.5 keV should 

be used for identification and quantification of iodine radioisotopes. 

 Section 8.20 was added to include calibration standards in the listing of reagents 

and materials. 

 Section 11 was re-written to fully detail calibration and acceptance criteria 

requirements for the high-resolution gamma-ray spectroscopy system. The rewrite is very comprehensive in comparison to the calibration section in D 4785-

00a. 

 Section 13.3.6 was updated to include a new table (Table 1) for iodine 

radioisotope nuclear decay data. Table 1 provides the gamma energy, gamma 
11

fraction, and half-life for the radioactive iodine isotopes (121I, 123I, 124I, 125I, 126I, 

129I, 130I, 131I, 132I, 133I, and 135I) applicable to the method. 

 Section 14 was re-written to incorporate MARLAP calculations as noted below: 

- Section 14.1calculates the net count rate and standard uncertainty of each 

photopeak. 

- Section 14.2 was updated for the activity calculation to include the gamma 

emission probability Iγ for the iodine isotopes listed in Table 1. 

- Section 14.3 calculates the uncertainty due to counting statistics. 

- Section 14.4 calculates the CSU to include the standard counting uncertainty, 

relative standard uncertainty of the measured quantity, and the relative 

standard uncertainty due to other causes identified by the user. 

- Section 14.4 was updated to replace the expanded uncertainty with Section 

14.5, which updates the calculation to MARLAP. 

- Section 14.6 was added to provide for the calculation of the critical activity 

concentration (Lc). 

- Section 14.7 replaces Section 14.5 (in D 4785-00a) for the calculation of 

minimum detectable concentration (MDC). The new calculation is consistent 

with MARLAP. 

 Section 15 has been rewritten as noted below: 

- Section 15.1 defines the QC program for the instrument and details the size of 

an analytical batch to be limited to 20 samples. 

- Section 15.2 describes the carrier recovery acceptance criteria for the internal 

stable iodide standard used in the determination of radioiodine in each sample. 

- Section 15.3 details calibration and calibration verification steps. 

- Section 15.4 describes the steps necessary for initial demonstration of the 

laboratory/instrument/analyst capability. 

- Section 15.5 details laboratory control sample requirements in analytical 

batches. 

- Section 15.6 provides for method blank requirements in an analytical batch. 

- Section 15.7 describes the requirements for analytical batch matrix spikes. 

- Section 15.8 presents the requirements for duplicates in the batch analysis. It 

also delineates the duplicate error ratio calculation and acceptance criteria. 

- Section 15.9 defines the requirements for quarterly verification of the 

quantitative value produced by the test method by analyzing independent 

reference material that has been submitted on at least a single-blind basis. 

 Section 16.4 was updated to reflect the addition of the new Table 1 in Section 

13.3.6; the table in Section 16.4 is now Table 2. 

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of 

iodine concentrations has been updated to capture the uncertainty determinations outlined 

in MARLAP. The precision and bias are unchanged for iodine-131. The QC 

requirements in D 4785-08 are far more detailed than those cited in D 4785-00a. 

Therefore, Method D 4785-08 is considered to be equally as effective as D 4785-00a for 

determining iodine concentrations in drinking water. 
12

6) ASTM International Method D 5174-07:

Method D 5174-02 was used as the basis for comparison, because it is currently promulgated in 

the drinking water regulations at 40 CFR 141.25(a) for determining uranium in water. The 

following changes are included in the newer version: 

 Section 1.1 was modified to change the lower end of the calibration range from 

0.05 ppb or greater to 0.1μg/L (0.1 ppb) or greater. 

 Section 2.1 was modified to update referenced ASTM standards; Standards D 

4448 and D 6001 were added. 

 Section 6.4 was modified to remove Fluran as a complexation agent. Uraplex is 

the only remaining polyphosphate. 

 Section 6.6 was modified to specify the molarity of the nitric acid used (0.8 M) 

for diluting samples if they exceed the calibration range. 

 Section 6.7 was added to further explain how to minimize the effects of 

interferences by diluting the sample with 0.8 M nitric acid. 

 Section 7.1.1 was changed to raise the method detection limit (MDL) from 0.05 

μg/Liter to 0.1 μg/Liter. 

 Section 7.1.3 was modified, to change the precision statement, from“The 

precision of repetitive measurements must be within 15% relative standard 

deviation (R.S.D.).” to “The precision of repetitive measurements sufficient to 

obtain a relative standard deviation of less than 15% at the low points of the 

calibration curve.” 

 Section 10.1 was modified to add reference to ASTM Standards D 4448 and D 

6001 for the collection of non-drinking water samples. 

 Section 11.6 was modified with the addition of Note 4, which elaborates on how 

to minimize interference quenching effects by diluting the sample with 0.8 M 

nitric acid when lifetime values are below 200 micro seconds. 

 Section 12 has been rewritten to add and expand details on the following: 

- Performing and calculating the MDL on a periodic basis. 

- Determining the reporting limit (RL). 

- Reporting analytical results. 

 Section 14.2.2 was expanded to include delineation of the calibration verification 

concentration ranges, which were not present in D 5174-02. 

 Section 14.6.1 was modified, for method blank acceptance criteria, from “The 

concentration of analyte found in the blank should be less than half the MDC.” to 

“The concentration of the analyte found in the blank should be less than the 

reporting limit.” 

 Section 14.7.3 was modified to clarify that the matrix spike recovery calculation 

is in percent recovery. The calculation terms were changed, but the calculation 

remains the same.

 Section 14.7.4 was modified to change the acceptance criteria for matrix spike 

recovery from 50% of the expected value to a range of 50% to 150% of the 

expected value. 
13

The two methods are identical with respect to drinking water sample collection/handling 

protocols and sample preparation, and are analytically equivalent. The calculation of uranium 

concentrations has been updated to expand determination of the MDL and RL. The precision 

and bias are unchanged. The QC requirements in D 5174-07 are more detailed than those cited 

in D 5147-00a. Therefore, Method D 5147-07 is considered to be equally as effective as D 

5147-02 for determining uranium concentrations in drinking water.