Sample Acceptance Policy

GBRA Lab Sample Acceptance Policy indicates the minimum conditions a sample must meet on receipt at the laboratory. Sample collection personnel are to use water resistant ink, use appropriate sample containers, adhere to holding times, and sample volume requirements. Deviations from the Sample Acceptance Criteria will be documented on a GBRA Non-Conformance form and/or the Chain of Custody (CoC), as well as the final report.

The laboratory by checking samples for the following qualities for chemical and bacteriological samples, where appropriate, to evaluate sample acceptance:

  • Thermal preservation – The sample temperature must be between 0-6°C. Samples delivered to the lab the same day as they are collected are not likely to have reached a fully chilled temperature. Samples shall be considered acceptable, without qualification, if there is evidence the chilling process has begun. The temperature for each sample and presence of ice will be recorded on the CoC.
  • pH check – The pH of samples requiring acid/base preservation is checked upon sample receipt and documented on the CoC, along with any preservation performed by the laboratory.
  • Chlorine check – All (Drinking water, non-potable and construction) bacteriological samples must be submitted to the laboratory in approved sample containers. Containers are available upon request. The client is responsible for recording the Chlorine Residual on the CoC. If Chlorine Residual is not indicated a qualifier will be added to the final report.
  • Sample integrity – All samples are checked for sample integrity with the following criteria:
    1. Approved container based on the type of analysis requested.
    2. Cracks, leaks, possible contamination and/or any factors that could affect the integrity of the sample.
    3. Adequate sample volume and air space.
    4. Hold times for requested analysis must not be exceeded.
  • Chain of Custody (CoC) – Information on the CoC must be properly and fully completed. Sample collectors are urged not to utilize photocopies of CoCs. We prefer that the customer fill out the necessary information by hand, when possible.

If the checks performed upon sample receipt indicate the criteria are not met, then:

  1. The sample custodian will place a call or email the client for instruction.
  2. The decision to proceed is documented on the non-conformance form and agreed upon with the client. In the event the client cannot be contacted immediately, the sample(s) is placed on "hold" status. We will not log in the sample until we are given instruction by the client and instructions are documented accordingly. If there is no response within 3 working days the sample is automatically rejected.
  3. Subsequent client contact to address the sample conditions are also documented on a non-conformance form or CoC and the sample is processed accordingly. (emails/phone calls or faxes)
  4. A Q (Qualifier) will appear on the final report with a brief explanation if the sample criteria have not been met.
© 1998 Guadalupe-Blanco River Authority