How to Collect A Sample

Tarrant County - Home > Public Health > Disease Control and Prevention > North Texas Regional Laboratory > Water Testing > Water Bacteriology Testing > How to Collect A Sample

Follow the proper procedure for testing: unless your sample is collected in a bottle provided by our laboratory and every precaution is taken to avoid contamination, the results of the lab analysis are without value and your drinking water may be UNSAFE.

Step 1 - After getting the required bacteriology kit from our lab; find the proper location.

  1. Use an outside faucet which does not leak (avoid rubber hoses, fire hydrants and dirty areas.) Remember to take only one sample per location, per time.
  2. Flame the mouth of the faucet with a propane torch or swab the mouth of the tap with a 10% bleach solution.
  3. Run the water two to three minutes to clear the line.
  4. Adjust the flow to a slow, steady stream.

 

Step 2 - Sample carefully.

  1. Carefully remove the cap of the water bottle and fill to the 120 ml line located closest to the top of the bottle. IMPORTANT - Do not touch the inside of the bottle or put the bottle on the ground. Do not overfill or underfill the bottle or the samples will be rejected.
  2. After filling the bottle, replace the cap securely and put the sample in ice immediately after collection.

 

Step 3 - Get it to the lab in a hurry.

  1. Fill out your portion of the form completely and if you are a public water system be sure to include your PWS number.
  2. If you chlorinate, record your chlorine residual prior to collection.
  3. Make sure the lab has no reason to reject the sample before analysis. Look at the rejection criteria at the bottom of the form.
  4. IMPORTANT - Prior to mailing or carrying the sample and lab form to the lab, the sample must be placed in ice. Please make sure the form does not come in contact with melted water from the ice. (PLEASE DO NOT FREEZE SAMPLE)
  5. Your sample MUST arrive in the lab less than 24 hours from the time you take the sample.
  6. If you are a public water system, attempt to get samples to the lab as early as possible in the month.

 

We accept samples Monday-Thursday. Samples should be received in the laboratory no later than 5 p.m. For an additional $15 weekend service charge, we will accept samples before 4 p.m. on Friday and the day before a county holiday.

 

The laboratory is closed on all legal holidays. Samples are not accepted on these days. The day before a holiday is an additional $15 service charge. To verify holiday closings, please call the lab at 817-321-4778.