Sampling and sample handling for BOD

Water and wastewater samples are biologically active, and the BOD will quickly deteriorate. Minimize the time between sampling and analysis to obtain the best BOD results. Take the following precautions when sampling and handling BOD samples.

Record the composite sampler temperature in permanent ink daily!

Sampling considerations

• Preferably sample before any disinfection.
• If sampling after any disinfection, samples must be seeded.

Handling considerations

• Composite samples must be kept at 0 - 6°C.
• Cool samples on ice between the composite sampler and laboratory.
• Maximum holding time is 48 hours for both grab and composite samples.
  • Composite samples - this means 48 hours after the sample is removed from the auto-sampler.
  • Recommended grab sample holding time is 6 hours (Standard Methods).

Copyright 2006. University of Wisconsin Board of Regents.
Unauthorized use prohibited without the expressed written consent of the UW, State Laboratory of Hygiene and the Wisconsin DNR- Laboratory Certification & Registration Program.

Contact information

For information on the Lab Certification program, contact:

Tom Trainor
Program chemist
Certification Services

DNR LabCert mailbox