How exact does the time of analysis need to be?
The time of analysis, along with the time of collection in the field, are needed to assess holding times for each sample. Automated data review compares this information to holding time requirements in the project library, which are based on EPA and DEP rules. The more exact the time, the better. For example, automated methods should stamp the exact time of analysis. Manual methods can have the exact time written by the analyst or the end time of the analytical run as the time of analysis for all samples. If a specific sample will expire during the run (start at 1 PM and go to 3 PM with one sample expiring at 3:00 PM), then one should put the exact time of analysis for that sample or it will be flagged as out of holding time.
