project-1-BACT Testing.pdf

Bac‐T Testing o In accordance with AR 200‐1 use of standard method 9221 B (Total Coliform) and 9221 F (Coliilert) o Samples taken in accordance with EPA Standards

Total coliform and E. coli (Escherichia coli) are used as indicator organisms for fecal or sewage contamination.

Detection of total coliform and E. coli in water, food or surfaces usually points to poor hygiene and possible presence of pathogenic organisms.

Proper procedures for collecting samples must be observed to ensure that the samples are representative of what is being tested, i.e., water, food or surfaces. A competent person shall perform sampling and deliver the samples to an approved Laboratory for testing.

To avoid unpredictable changes in the bacterial composition or concentration of the samples, analysis should be started as soon as possible after collection. The sample should be transported to the laboratory in a cooler containing ice or cooling packs. It is important that samples are protected from direct contact with the ice or cooling packs to prevent freezing during transport. If possible the interval between sample collection and the beginning of its analysis (i.e., holding time) should not exceed 24 hours. In remote areas, however, this may not be possible and up to 48 hours may be an accepted holding time. The implications of the extended holding time should be discussed with the laboratory.

Samples should be labelled so that they are easily identified. Complete the chain‐of‐custody form with the time, date, location, type of sample (e.g., raw water, building number/room number sink location), sampler’s name, and identification number, and any special instructions. If the holding time is more than 24 hours for whatever reason it is important to record the duration and temperature of storage, as this information should be taken into consideration when interpreting the results.

Instructions for sampling water for Total Coliform and Escherichia coli (E.coli) testing Proper sampling procedure is extremely important in obtaining accurate water testing results. It is recommend using the sample containers provided by the testing lab. Before you begin sampling, please read all of these instructions. Remember, do not remove the cap from the bottle until just before you are ready to sample.

1. Before collecting a sample for bacteriological analysis, you must first obtain a STERILE SAMPLE BOTTLE and the chain of custody.

2. Select a cold water tap that is used frequently, but avoid using the kitchen sink faucet if at all possible. If the sampling tap has a screen or an aerator, please remove it. If you are using an outside tap, disconnect any hoses or other attachments.

3. Run the cold water at a relatively high flow for 3 to 6 minutes to clear the line. Reduce the flow to a smooth‐flowing water stream so it doesn’t splash.

4. Carefully open the bottle, keeping hands away from the inside of the cap or the bottle rim. The white powder or tablet must remain in the bottle. DO NOT RINSE THE BOTTLE. Fill bottle to three‐quarters full. A minimum of 300 ml sample is required. If overfilled, DO NOT POUR OUT EXCESS.

5. Fill out the label attached to the bottle with the required information.

6. Complete the chain of custody form, fold it and put it in a plastic bag to prevent it from being damaged by the ice packs.

7. Your sample must be kept cool at all times and must be received by the laboratory within 24 hours (if possible) from the time of “collection”. All samples must be kept cold and brought to the laboratory in a cooler or on ice packs.