ACT pH Sensor Verification Protocols, PV12-01
11
sheets
are done
reference method
Performance
evaluation audit
results
ACT HQ
Laboratory record
books/data
sheets
At times of
performance
evaluation audits
Test reference method
with independent
standards/
measurements
7.2.
Data Review
Data to be reviewed by the ACT Partner test facility will include electronic data, entries
in field/laboratory record books, operating data from test facilities, and equipment calibration
records. All manually recorded data are to be recorded directly in the field/laboratory record
book as soon as they are available. Records are to be written in water-proof ink, written legibly,
and have any corrections initialed by the person performing the correction. Any corrections will
be crossed out with a line (not blackened or white-out), and the correction made, with initials and
date of correction. Records will be spot-checked daily to ensure that the data are being recorded
correctly. The checker shall not be the individual who originally entered the data. All data
entries will be checked for obvious errors, and a minimum of 10 percent of all records shall be
checked in detail. Errors detected in this manner shall be corrected immediately. The person
performing the review will add his/her initials and the date to a paper copy of the record being
reviewed. The ACT Technical Coordinator (TC) will place this paper copy in the files for this
Verification. In addition, data generated by each ACT Partner test site will be provided to the
ACT Chief Scientist for review before they are used to calculate, evaluate, or report results.
8.0
Quality Assurance
The ACT quality assurance system includes training, documentation, quality control, and
quality assessment. Quality control includes those procedures that ensure that data generated
from ACT verifications are of known accuracy and meet data quality goals. Quality assessment
s
provide assurance that quality control is being done effectively. Quality assurance and quality
control procedures for this pH Sensor Verification will follow the requirements described in
these Protocols, any vendor specified requirements, and the general principles and specific
QA/QC from technical documents for measuring pH in aquatic systems (e.g., Dickson et al.,
2007).
8.1
Laboratory Quality Control Requirements
Quality control measures undertaken to assure the reliability of the data collected, and
described above in the sampling design section, include:
•
Duplicate sampling to ensure sample representativeness with respect to sampling and
handling procedures. The acceptable range of relative percent difference between a sample
and its duplicate is 20% unless specified otherwise in a specific test plan.
•
Replicate analysis to ensure sample representativeness with respect to sample processing and
analysis. The acceptable range of relative standard deviation among replicate analyzes is
10%.
