Troubleshooting water sampling

If the pipettor does not deliver exactly 100 pi (check by weighing an aliquot of water see Critical Parameters and Troubleshooting), it should not affect the final result since the same amount will be used in all three portions. The same micropipettor must be used for the glucose standard and samples. Do not use oversized tips (e.g., 500 or 1000 pi), since this leads to increased error. Precise pipetting is critical for accuracy of results (see Critical Parameters and Troubleshooting). 

Using this or similar mixtures, inject a sample into an equilibrated column, elute the resolved bands, and record them on the recorder. Calculate plate counts for the first and last peak using the 5 [Pg.38]

Figure 13.15 shows the operational scheme of this automatic tltrator. The heart of the unit Is an INTEL 8080 microprocessor mounted on the central processing unit (CPU) board. The rotary reaction cell assembly can accommodate up to three different sensors for multiple measurements on the same processed sample. Each stepper burette board controls up to two burette dispensing assemblies. Function boards such as the colorimeter board, air burette board, E/I output board and RS-232 printer Interface boards are available optionally. The optional D/A and E/I board is used for closed-loop applications where the tltrator controls the final element such as a control valve. The RS-232 printer Interface board Is useful for troubleshooting the equipment and editing user-defined programs. The Instrument accuracy, repeatability and response time vary widely and depend on the particular type of measurement concerned. The system requires a.c. power, a 75-psl air supply and a dilution water supply for proper operation. The air flow-rate required is of about 50 cm3/mln... 

On July 8 and 9, 1992, with the unit at no greater than 10% power, work crews at Limerick Unit 1 were performing troubleshooting on a main steamline sample flow isolation valve inside the drywell. The crews were unaware that a narrow, intense beam of radiation passed from a reactor water level instrumentation penetration to the inner drywell wall near the work area. The beam measured 6" at the penetration to 1 -2 at the drywell wall. The beam was discovered when the dosimeter of one worker alarmed. 

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