IOP:012.0I INSTRUMENT OPERATING PROCEDURE
Contents
1. B a7 mon Collect a stream water sample containing TFM Prepare the water sample for analysis 1 Add 1 mL sodium tetraborate buffer to a 250 mL stream water sample and shake 2 Filter the sample into the cuvette with a syringe filter 3 If problems with cuvette fogging occur adjust the sample temperature by placing the 10 mL cuvette into the water bath or by holding in the hands Insert the blank into the sample cell holder Press A to Zero the instrument Wait until 0 000 ABS is displayed Dry the sample cuvette with a tissue and insert into the sample cell holder Close the light shield door and press the right select key to Read the sample Record the measured absorbance on the LAMPRICIDE ANALYSIS DATA FORM Appendix M Subtract the background absorbance base blank on the data sheet and record Divide the resulting absorbance by the calculated slope of the calibration curve Record the result as the concentration of TFM mg L in the stream water sample VII Documentation A Make entries into instrument log book each time instrument is used B Record results of analysis on LAMPRICIDE ANALYSIS DATA FORM Appendix M MAINTENANCE I Cleaning instrument see page 14 of the DR1900 Basic User Manual Il Battery replacement See page 7 of the DR1900 Basic User Manual A Loosen the 4 screws securing the battery compartment cover on the underside of the unit B Remove the cover and old batteries C Insert 4 charg2. absorbance are conducted to assure accuracy of analyses d Water samples are buffered to pH 9 0 before measurement of absorbance e Water samples are filtered before measurement of absorbance f Record keeping requirements are the same 2 Difference a Similar to DR2800 analyses water samples are not normally heated before analysis The accuracy of measurements depends to some degree on the comparative absorbencies of the optically matched sample cells in each DR1900 kit The method of data interpretation used during TFM analyses demands that special attention is given to compensation for poor matches when they cannot be avoided The recommended setup for typical field use is the DR1900 instrument with 4 charged AA nickel metal hydride NiMH batteries installed The instrument can also be used with 4 AA alkaline batteries or on line power using the Power Module LZV804 If a firmware update is required the USB Power Module LZV813 is used instead of the Power Module Initial Instrument Setup A Assembly and initial startup 1 Unbox the DR1900 spectrophotometer and Power Module as well as 4 AA NiMH batteries Battery installation See page 7 of the DR1900 Basic User Manual a Charge NiMH batteries using an appropriate charger b Loosen the 4 screws securing the battery compartment cover on the underside of the unit and remove the cover b Insert 4 charged NiMH batteries in the orientation indicated inside the
3. p Lf fi j 1 4 REVIEWED APPROVED 1o__ S SO DATE Mat S S en k L O nn Division Manager Canada
4. to enter the Options menu 2 Use the A and V navigation buttons to highlight TA Abs Conce and press the right Select button 3 Use the A and V navigation buttons to move the black circle into the Abs position and press the right select button OK to save changes The instrument will return to the home screen and should now be ready for single wavelength absorbance measurements at 395nm E Set the resolution 1 From the Home screen in Single Wavelength mode press the left select button to enter the Options menu 2 Use the A and WV navigation buttons to highlight Advanced Options and press the right Select button 3 Use the A and V navigation buttons to highlight Resolution and press the right Select button Use the A and V navigation buttons to move the black circle into the 0 001 position and press the right select button OK to save changes 4 Press the Home button lower right to return to the home screen M Analysis Preparation A Charge 4 NiMH batteries prior to field use Set up the spectrophotometer in a shaded location Always close the light shield door when making absorbance measurements B Use line power if available however use of this instrument is normally reserved for situations in which line power is not available C After all peripheral equipment for sample preparation is ready press and briefly hold the POWER button W located on the bottom center of the keypad The instrument will conduct internal tes
5. Always use the same cell for the 0 0 standard blank VI G Prepare the TFM free water sample for analysis 1 Add 1 mL sodium tetraborate buffer to a 250 mL stream water sample and shake 2 Filter the sample into the cuvette with a syringe filter Generally syringe filters should be replaced after being used between 4 to 6 times Filters can be used until resistance is felt which may be one use on a stream with high total suspended solids to many uses on a stream with low total suspended solids 3 Adjust the sample temperature by placing the10 mL cuvette into a water bath or by holding in the hands Insert the blank into the sample cell holder and close the light shield door Press A to Zero the instrument Wait until 0 000 ABS is displayed Dry the sample cuvette with a tissue insert into the sample cell holder close the black outdoor light shield and press the right select key to Read the sample Note the measured result on the analysis form This absorbance includes both the background absorbance of the stream water and the difference in absorbance between the blank and sample cells Do not correct this value for differences between cells even if it is significant If the difference between cells was considered significant when checked compensation was made when producing the calibration curve Determine the B A ration for the stream water at the site according to procedures outlined in TOP 018 x Sample measurement A
6. IOP 012 01 U S Fish and Wildlife Service March 18 2015 Marquette Biological Station 3090 Wright Street Marquette Michigan 49855 U S A and U S Fish and Wildlife Service Ludington Biological Station 229 South Jebavy Drive Ludington Michigan 49431 U S A and Fisheries and Oceans Canada Sea Lamprey Control Centre 1219 Queen Street East Sault Ste Marie Ontario P6A 2E5 Canada INSTRUMENT OPERATING PROCEDURE INSTRUMENT Spectrophotometer MODEL DR1900 with power module LZV 804 or USB power module LZV813 MANUFACTURER Hach SERIAL AND PROPERTY NOS DR1900 01 MBS 141700001005 3275 DR1900 01 MBS 141700001006 3276 MBS MBS priom stec 141940001009 1466 o Room sree aooo eri PRECAUTIONS POTENTIAL INTERFERENCES None listed in manual SAFETY No special safety precautions PROCEDURES I Il Background A The Hach DR1900 is capable of direct readout of concentrations of TFM however this option does not support the requirements of methods of analysis developed for line powered spectrophotometers The procedures for analysis with the DR1900 closely parallel those used with the DR 2800 and Genesys 20 spectrophotometers 1 Similarities a Pre formulated standards with concentrations of 0 4 8 and 12 mg L TFM are used b The slope of the instrument response is determined through measurement of the absorbance of the TFM standards c Base Acid measurements of background
7. compartment c Replace the cover and tighten the screws sufficiently to ensure IP67 waterproof rating Remove the cover from the Power Module remove the blank module from the DR1900 and insert the Power Module into the DR1900 Power Module slot Plug the power cord included with the Power Module into the module and an outlet to power the unit Press and briefly hold the POWER button located on the bottom center of the keypad to turn the instrument on Use the A and WV navigation buttons to move the black circle to English and press the right select button OK to save changes Use the A and V navigation buttons to highlight mm dd yyyy 24h and press the right select button Select to save changes Use the A and V navigation buttons to set the date and time values Use the lt 4 and gt navigation buttons to move between settings Once all values are set press the right select button Ok to save changes NOTE all of these settings can be accessed and changed later by pressing the button with an image of a wrench lower left using the A and Y navigation buttons to highlight Setup pressing the right select key Select using the A and Wnavigation buttons to highlight the appropriate parameter pressing the right select key Select using the A and Y navigation buttons to edit the value and pressing the right select key Select to save the modified setting Press the Home button lower right to go to the home screen The ins
8. ed NiMH or alkaline batteries in the orientation indicated inside the compartment Test batteries for compatibility units were found not to function with standard Rayovac alkaline batteries when standard Energizer alkaline batteries worked D Replace the cover and tighten the screws sufficiently to ensure IP67 waterproof rating Press and briefly hold the POWER button W located on the bottom center of the keypad The instrument will conduct internal tests F The power indicator upper right corner of screen should show about 80 charge if the NiMH batteries are fully charged When alkaline batteries are used a new battery will show 100 charge G The instrument should boot up in single wavelength mode and display Single Wavelength and 395nm in the top status bar of the screen If the instrument boots in a different program see Procedures subsection II of this IOP MI Firmware update See page 11 of the Power Module User Instructions The USB Power Module LZV813 is required to perform firmware updates IV Troubleshooting see page 15 of the DR1900 Basic User Manual REFERENCE Hach DR1900 Basic User Manual 2100Q DR1900 Power Modules User Instructions This procedure has been reviewed and approved by the undersigned representatives of the U S Fish and Wildlife Service and Fisheries and Oceans Canada ii 1 iT a i REVIEWED APPROVED mmni D Meie DATE 324 12 Field Supervisor U 5 ra i
9. o not allow the standards to sit in sunlight while in use and store the standards in the dark If the standards are very cold apt to fog warm them in a water bath or in the hands Insert the cuvette that contains the blank close the light shield door and press A to Zero the instrument Wait until 0 000 ABS is displayed Insert the 0 0 mg L TFM standard and close the light shield door Press the right select key to Read the sample The 0 0 standard may produce a reading other than 0 000 because of an imperfect match of cuvettes If the cells are not suitably matched subtract the difference due to cell mismatch noted above and record in log book Again insert the cuvette containing the blank and close the light shield door Wait until 0 000 ABS is displayed insert the 4 0 mg L standard and close the light shield door Press the right select key to Read the sample Again adjust the result for differences in absorbance between blank and sample cells if necessary Record the corrected absorbance in the instrument log book Repeat the procedure with 8 0 and 12 0 mg L TEM standards Divide the recorded absorbance of each standard by the concentration of TFM mg L 4 0 8 0 and 12 0 Average the results and record the mean in the log book and on the LAMPRICIDE ANALYSIS DATA FORM Appendix M Calibration stream water sample A Measure the background absorbance and B A ratio of the stream water TOP 018 x Do not interchange the cells
10. trument will conduct internal tests Program for single wavelength measurements 1 If the instrument is not already turned on press and briefly hold the POWER button W located on the bottom center of the keypad to turn the instrument on The instrument will conduct internal tests Press the button with an image of a wrench lower left to enter system setup Use the A and WV navigation buttons to highlight Photometric functions and then press the right Select button Use the A and WV navigation buttons to highlight Single Wavelength and then press the right Select button The instrument will return to the home screen and display Single Wavelength and nm in the top status bar of the screen Program wavelength to 395 nm 1 From the Home screen in Single Wavelength mode press the left select button to enter the Options menu Use the A and V navigation buttons to highlight Advanced Options and press the right Select button Use the A and F navigation buttons to highlight nm and press the right Select button Set the wavelength to 395 by using the A and W buttons to change the value of the highlighted digit and the lt and gt buttons to switch between digits Once the wavelength is set to 395 press the right select button OK to save changes The instrument will return to the home screen D Set the readout to absorbance 1 From the Home screen in Single Wavelength mode press the left select button
11. ts D Make sure that the power indicator upper right corner of screen shows at least 34 power IV The instrument should boot up in single wavelength mode and display Single Wavelength and 395nm in the top status bar of the screen If the instrument boots in a different program see Procedures subsection II B E of this IOP Match the 10 mL sample cells 1 Open a new 0 0 mg L standard and rinse and fill two factory matched 10 mL sample cells 2 Place the first cell in the sample cell holder with the 10 mL mark facing forward and close the light shield door Press A to Zero the instrument Zeroing will be displayed until the instrument is zero calibrated 0 000 ABS will appear on the display when the instrument is zero calibrated 3 Place the second cell in the sample cell holder with the10 mL mark facing forward and close the light shield door 4 Press the right select button Read 5 The sample cell should produce an absorbance less than 0 008 considered an acceptable match maximum 0 05 mg L error If the difference is greater clean the cell or check the absorbencies of spare sets of matched cells If an acceptable match cannot be obtained and another matched set is not available note the absorbance difference so absorbencies of standards can be corrected The cell with the lesser absorbance is used as the blank Calibration standards A Open the remainder of the new set of TFM standards D
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