BACTERIAL SAMPLING* - Biovir

1 BACTERIAL SAMPLING* Biovir Laboratories, Stone Road, Unit 6, Benicia, CA 945101-800-442-7342 (Fax ) 707-747-1751E-Mail: Craig Johnson @ Site: ContainersCollect samples for microbiological examination in bottlesthat have been cleansed and rinsed carefully, given a final rinsewith distilled water, and sterilized. (Please refer to StandardMethods for the Examination of Water and Wastewater, 18thedition) for wash and sterilization protocols. Alternatively,purchase pre-sterilized containers and integrity check eachsealed vessel prior to DechlorinationAdd a reducing agent to containers intended for thecollection of water having residual chlorine or other halogenunless they contain broth for direct plating of sample.

2 Sodiumthiosulfate (Na2S2O3) is a satisfactory dechlorinating agent thatneutralizes any residual halogen and prevents continuation ofbactericidal action during sample transit. Alternately, purchasepre-sterilized containers appropriate for thevolume of sample desired which contain Sodiumthiosulfate in pellet form. The examination thenwill indicate more accurately the true microbialcontent of the water at the time of drinking water samples, the concentra-tion of dechlorinating agent: mL of a 3%solution of Sodium thiosulfate in a 120-mL bottlewill give a final concentration of 18 mg/L in thesample and will neutralize up to 5 mg/L residualchlorine.

3 In emergency disinfection with higherconcentrations of chlorine add sufficient dechlori-nation agent to give a concentration of 100 mg/L inthe Collection - General1. When the sample is collected, leave ample air space inthe bottle (at least cm) to facilitate mixing by shaking, Collect samples that are representative of the waterbeing tested, flush or disinfect sample ports, and use aseptictechniques to avoid sample Keep sampling bottle closed until it is to be Remove stopper and cap as a unit. DO NOT contami-nate inner surface of stopper or cap and neck of Fill container without Replace stopper or cap immediately, and if used,secure hood around neck of bottle.

4 Alternately, secure tamperproof devices applicable to sample Collection - Potable WaterIf the water sample is to be taken from a distributionsystem tap without attachments, select a tap that is supplyingwater from a service pipe directly connected with the main, andis not, for example, served from a cistern or storage tank. Opentap fully and let water run to waste for 2-3 minutes, or for a timesufficient to permit clearing the service line. Reduce water flowto permit filling bottle without splashing. If tap cleanliness isquestionable, apply solution of sodium hypochlorite (100 mgNaOCl/L) to faucet before sampling; let water run for additional2 to 3 minutes after treatment.

5 Do not sample from leaking tapsthat allow water to flow over the outside of the tap. In samplingfrom a mixing faucet remove faucet attachments such as screenor splash guard, run hot water for 2 minutes, then cold water for2 to 3 minutes, and collect sample as indicated the sample is to be taken from a well fitted with a handpump, pump water to waste for about 5 minutesbefore collecting sample. If the well isequipped with a mechanical pump, collectsample from a tap on the discharge. If there isno pumping machinery, collect a sampledirectly from the well by means of a sterilizedbottle fitted with a weight at the base; take careto avoid contaminating samples by any drinking water evaluation, collectsamples of finished water and from distributionsites selected to assure systematic coverageduring each month.

6 Carefully choose distribu-tion system sample locations to include dead-end sections todemonstrate bacteriological quality throughout the network andto ensure that localized contamination does not occur throughcross-connections, breaks in the distribution lines, or reductionin positive pressure. Sample locations may be public sites(police and fire stations, government office buildings, schools,bus and train stations, airports, community parks, commercialestablishments (restaurants, gas stations, office buildings,industrial plants))

7 , and buildings, and townhouse complexes,and special sampling stations built into the distribution sampling program in consultation with state and localhealth Collection - Raw Water SupplyIn collecting samples directly from a river, stream, lake,reservoir, spring, or shallow well, obtain samples representativeof the water that is the source of supply to consumers. It isundesirable to take samples too near the bank or too far fromthe point of drawoff, or at a depth above or below the point SAMPLINGBioVir Laboratories, Stone Road, Unit 6, Benicia, CA 945101-800-442-7342 (Fax ) 707-747-1751E-Mail: Craig Johnson @ Site.

8 Collection - Surface WatersStream studies may be short-term, high-intensity bacteriological sampling locations to include a baselinelocation upstream from the study area, industrial and municipalwaste outfalls into the main stream study area, tributaries exceptthose with a flow less than 10% of the main stream, intakepoints for municipal or industrial water facilities, downstreamsamples based on stream flow time, and downstream recre-ational areas. Dispersion of wastewaters into the receivingstream may necessitate preliminary cross-section studies todetermine completeness of mixing.

9 Where a tributary stream isinvolved, select the sampling point near the confluence with themain stream. Samples may be collected from a boat or frombridges near critical study points. Choose sampling frequencyto be reflective of stream or water body conditions. For example,to evaluate waste discharges, sample every 4 to 6 hours andadvance the time over a 7 to 10 day monitor stream and lake water quality establishsampling locations at critical sites. Sampling frequency may beseasonal for recreational waters, daily for water supply intakes,hourly where waste treatment control is erratic and effluents aredischarged into shellfish harvesting areas, or even Collection - Bathing BeachesSampling locations for recreational areas should reflectwater quality within the entire recreational zone.

10 Include sitesfrom upstream peripheral areas and locations adjacent todrains or natural contours that would discharge stormwatercollections or septic wastes. Collect samples in the swimmingarea from a uniform depth of approximately 1 meter. Considersediment sampling of the water-beach (soil) interface becauseof exposure of young children at the water s obtain baseline data on marine and estuarine bathingwater quality, include sampling at low, high, and ebb Collection - Sediments and SludgesThe bacteriology of bottom sediments is important in watersupply reservoirs, in lakes, rivers, and coastal waters used forrecreational purposes, and in shellfish-growing waters.