Check Instrument Zeros and Take Pictures Esp Cracked TEOM Inlet Assembly

26th December 2003 Friday 13:15 Operators : KB Check instrument zeros and take pictures [esp cracked TEOM inlet assembly]. 1326 (LT): supply O3 cal 180 ppb from PS to both analyzers [ZA from compr air tank]. 1337: supply 120 ppbv. 1341: supply 80 ppbv, plus ZA to CO analyzer. 1352: supply 40 ppbv 1356: supply zero air [0 pbbv]. 1401: CO and O3 back to amb meas mode; supply ZA to NOx. 1407: set NO and NOx analog output to zero. 1414: NOx back to amb meas.

2nd January 2004, Friday Operators : KB, WY 1445: Finished setting CO zero level using zero trap. End result- zero level was 451.3 ppb too high. 1806: ZA to CO. Preset ZA MFC at 2345 sccm, CO cal flow at 4.678 sccm, concentration 2837 ppb. 1827: Automatic zero on 1830: Manual addition of cal gas (2837 ppb) so zero + cal 1833: Auto zero off 1840: Readout display 2172 ppb (~2.2 Vdc) 1846: Manual setting of span to 2837 ppb (~2.85Vdc) 1850: Manual override of CO-zero in span mode 1857: Display ~390 ppb, so zero trap not 100% efficient! (2837-390)/2837= ~86% 1902: Back to ambient CO 1906: Supply ZA to NOx 1910: Reads 0-1 ppb for NO + NOx; set to zero 1912: Supply cal gas from NO cal tank.; nominal concentration 10.13 * (4.678/2350)= 20.2 ppb [very slow!] 1930: Set Cal flow to 10.09 sccm, new nom. concentration 10.13 * (10.09/2355) = 43.4 ppb. No response after ~10 min. 1945: Switch over to NO2 cal gas. Tank is 99.8 ppm NO2 in N2, from 3/15/01. NOx nominal concentration 99.8 * (10.09/2355) = 427.6 ppb

5th January 2004- Monday KB 1300: Adding 2nd MnO2 zero trap for CO analyzer. Tried Dave Tanner’s ½” tube assembly first but too bulky, so use 2nd filter holder. 1400: Start cal on NOx flushing vigorously with NO; seems to help. Zeros well. 1530: New NO slope 2.186, NOx slope 2.052 (with 43.4 ppb nominal concentration) 1600: Supply ~428 ppb NO2 from 99.8 ppm NO2 cal tank; slowly increasing 1645: Let analyzer do conversion efficiency calc; result is 1.14, which is bogus, so set conversion efficiency to 1.000 by hand (1700). 1710: CO in zero air, ~420 ppb display, ~0.42Vdc. CO cal flow 265 on display, 5.47 sccm. CO nominal concentration 1425 * (5.47/2350)= 3317 ppb. 1720: Submit CO cal of 3317 ppb. Inverse span 3317 ppb / (3.1-0.42V) = 1238 ppbv/Vdc. 1726: Display ~ 3100 ppb, ~3.10Vdc. 1727: Turn on CO zero trap. 1732: Drop to 332 ppb, ~0.34V. Turn off CO cal valve and flush (results in a spike) 1739: Now 442 ppb, ~0.48Vdc. Turn off zero trap valve. 1750: Turn off zero air. Zero trap efficiency ~ 100%.

12th January 2004- Monday WY 14-1530: Playing with wiring to set up indoor air sample solenoids. Master 24Vdc supply interrupted, so there may be intermittent losses of BARO and CO zero. Current draws: CO zero solenoid: 290mA @24Vdc Indoor air sample solenoids (together): 450 mA @24Vdc 1530: Reprogramming DAQ for 1 Hz screen updates. It crashes, so I reboot. More reprogramming. Sequences won’t start until 1700. No indoor air sampling yet today; we have a bad SSR. Program is left driving an unconnected digital line. New output file name (RooftopLab….) 1617: Wiring activity causes a spike in all analog input channels. 1630: Done for today. Sequences start at 1700.

15th January 2004- Thursday WY, KB 1800: WY: Indoor/outdoor sampling connected for continuous gas analyzers using new SSR. There’s no stop-start because the programming was already done. I only had to connect the replacement SSR to the right places. 2/1/04 KB: from O3 record, it appears that the gas switching was every 5min with indoor sampling from minute 1-5, 11-15, 21-25, 31-35, 41-45, 51-55.

2300: KB installed three port, two way solenoid valve for TEOM indoor/outdoor sampling, and a third rotameter for bypass line. Plumbed so that still measures outdoors while valve not switching. TEOM in/out bypass pump line not strong enough to pull 16.7 lpm, so switch from sequential sampler piston pump to big carbon vane pump. Balance all flows so that 1) TEOM bypass flow is 16.7 lpm, 2) gas in/out has equal pressure as per O3 and CO pressure displays. The IN-cyclone is temporarily mounted outdoors ~1m away from regular TEOM inlet for comparison.

16th January 2004- Friday WY 1300: Connecting TEOM indoor/outdoor solenoid electrically. Has been sampling outdoor air by default. Readjusting rotameters; current regime seems to leave CO in particular with pretty low sample line pressures (22.8”Hg). I make some attempt to keep the TEOM’s bypass line at constant flow in the process, but can’t make any promises. 1400: Had to stop-start DAQ to implement the following changes. 1- Add absolute seconds readout to ContiGas graph. 2- TEOM and gas analyzers now on a ten minute indoor/ten minute outdoor cycle, as follows: “First whole hour:00” Begin outdoor :05- Begin indoor :15- Begin outdoor :25- Begin indoor :35- Begin outdoor :45- Begin indoor :55- Begin outdoor 1:05 (rel) Begin indoor… and so forth. It’s a constant 10min cycle except for the first five minutes.

We discover that API uses adaptive filters on their analog outputs to keep them smooth and pretty. The averaging time can go as high as two minutes when the concentration is steady, and decrease to as low as 10 sec when it’s changing. We don’t like this for our purposes, though! I call API and get instructions from Bob on how to speed up response time. He thinks the project is nifty, is glad to help, and thinks that the instruments will speed up plenty fast to achieve our goal. He advises that these settings are about as fast as we can go without picking up instrument artifacts and heavy noise. If the noise is too much at this level, double the filter sizes relative to his suggested numbers.

Speeding up CO response time: Press Setup, press More, press Vars. Enter password 929 Press Next until you reach “FILT_ADAPT”-> switch to OFF Press Prev until you reach “FILT_SIZE” -> reduce from 750 to 48 Exit.

1510: Manual CO zero to see results; much faster (under two minutes).

1515: Speeding up NOx response time: Press Setup, press More, press Vars. Enter password 929 Press Next until you reach “FILT_ADAPT”-> switch to OFF Find “FILTA_SIZE” and note value (was 6) Find “FILT_SIZE” and make it match FILTA_SIZE. So it changes from 42 to 6. Exit.

~1600(?): More programming revisions. We start logging a second conditional logged-process with a second file; it logs digital lines (only) at 1 Hz, and it really works. Then we realize we can add digital lines to our onscreen plots, so we do. They use dots instead of lines. We also change the CO zero, thanks to the fast response time, from being at n:24-n:30 to being from n:28-n:31.

1659: Final program restart before the weekend (accidental). KB starts the sequences (remotely) in a nick of time before 1700.

1 SCFH=0.473 lpm

1730: WY cleans up, packs up, goes downstairs.

19th January 2004 – Monday (MLK Holiday) KB ~1620 adjust TEOM naphion dryer bypass valve, so that TEOM out of flow alarm status (4). It was not able to maintain nominal 3 and 13.6 lpm sample (main) and bypass (aux) flows, probably due to increased restriction of the TEOM sample filter. Had to OPEN that valve one full turn in order to make it work without alarm. 1635 start relocating the cyclone head labeled “indoors” to inside; it has been sitting outside for comparison with the reg outdoors sample inlet. Mount it next to indoor gas line up at ceiling of room supply vent above instruments’ rack. 1649 restart DAQfactory program but noticed that it did not remember my changes made earlier of the CO zero start time [want it to start synchronized with the indoor valve switch at 25 min after the hour, in order to not lose too much real msmt data.

20th January 2004- Tuesday WY KB notes overnight that we have another TEOM flow alarm (alarm status 4) accompanied with ambT signal going full scale. WY visits 1100-1200 to check in. Filter load is 80%. No alarms are present at the time of visit. In playing around, we discover that the ambT signal seems to automatically go full scale whenever there is an alarm present. 1115: WY changes linearization of AmbT signal just in case there is a DAQ hardware problem. The old linearization from volts to degC was T=10V-50; now it’s T=8V-30. We also increase the TEOM’s temperature setpoints from 40 to 50 (except for the one that we leave at 0). WY also opens the nafion dryer-bypass valve one half turn. We think that the event we saw overnight was an actual flow problem- too much restriction through the nafion dryer for the pump to cope with 80% filter load- which actually caused the TEOM to make the ambT analog signal go crazy as an indication that there was a data quality problem (as related to the alarm). Hopefully allowing more bypass flow around the nafion dryer will prevent a recurrence. The pump is pretty new and a very durable design, so it should be strong enough. These changes (particularly changing the temp setpoints) make the TEOM take a very long time to equilibrate and come online again, and even then the data may indicate negative PM levels for a couple days as the filter burns off hydrates and water as it and the airflow heat up. We don’t know the actual flow or pressure in the nafion dryer sheath flow, but given how cold it is outside and that we’re running 50 C inside, WY doesn’t really think it’s of concern for the time being. We will have to see if the higher temp setpoints reduce the bounce in the mass concentration signal during clean conditions, or if we have to increase our indoor/outdoor cycle time for the TEOM to something more like 30 minutes instead of 10 minutes.

21st January 2004 – Wednesday KB remote 0140 check in remotely and notice that last CO zero, supposed to have happened at 1:25, did not show any response. 0146 Manually switched CO into zero mode and got good response. 0148 Manually out of CO zero. Need to watch CO zero valve, may be better to switch slightly offset in time rel to In/Out sample stream selector valve?!

23rd January 2004- Friday WY 1540: Making program changes to DAQ; TEOM’s indoor/outdoor sampling will now be outdoor from the top of the hour to nn:30, then indoor to the end of the hour. This takes effect at 1600. Restarting program to make change take effect… 1600: Changed TEOM’s inline bypass flow filter to hopefully improve the TEOM’s ability to maintain flow at high (sample) filter loads. This didn’t seem to have much effect. I checked the actual flow rate through the indoor sample line with the Dry-Cal while the TEOM was sampling outdoor air, and found it around 12 alm; I boosted it up to 16.7 at the rotameter for the TEOM in- out bypass suction (not the bypass that goes around the main sensor unit). Then I changed the TEOM filter. The filter load at the time was ~85%; after the change, it was 23%. None of these changes seemed to make a fundamental difference in how hard the TEOM has to work to maintain flow under high restriction conditions. I expect that we will again start to see intermittent flow problems when we exceed 80% or so.

26th January 2004 – Monday KB 1904 supply ZA to CO inlet (NOx sees it too!) at F = 111 (display) = 2345 sccm. 1908 add CO cal F = 265 (display) = 5.47 sccm (values assumed from 1/5 above). Hence CO nomC = 1425*5.47/2350 = 3317 ppbv. Reading stabilizes at about 3.12 V (from DAQ factory “CO” local channels list). 1914 switch into zero mode  ~2.4 V 1917 out of zero mode  ~3.05 V 1921 turn off CO cal F, and 1925 flush back with NO2 cal gas (spike in NOx reading!)  ~0.4 V, hence CO sens = 3317 / (3.08-0.4) = 1238 ppbv/Vdc (no change! See above) ZT eff = (3.08-2.4)/(3.08-0.4)*100 = 25 %. 1931 ZA off.

Exchange Carulite medium in both traps (filter holders); pore used carulite into a ss cylinder for regeneration in N2 under heat later (mainly water vapor makes carulite inefficient for CO). Make changes to DAQ program: Sample indoor gas at 0 min (valve energized), outdoor at 15 min, indoor at 30 min, etc, ie switch from 10 min to 15 min intervals to better line up with longer (30 min) TEOM intervals. This way, the last 15 min TEOM indoor correspond with gas indoor, and same for outdoor sample. Change CO zero to switch at 30 min and 5 sec for 3 min [was from 25 to 28 min of the hour].

2000 just missed restart of new DAQ settings, so it will start switching at 2100. TEOM FL = 36 %.

13th February, 2004 - Friday KB, WY Replace stream selector valve assembly [which was out of the old TEI O3 analyzer] with new 24 Vdc PFA-body 3-port 2-way valve [Galtec type]. Exchange ad hoc w/out interrupting or changing data system. Feels hot as usual when energized [indoor air]. Tee off on both indoor and outdoor sample lines, whereas outdoor tee is connected to the normally open port, and indoor tee to the normally closed port, common connected to manifold connecting to individual analyzers. Seems to switch well at ambient pressure, but not well in vacuum [ie we have ~25.6 inHg at CO, 28.0 inHg at NOx, and 720 Torr at O3. Install old TEI O3 analyzer in place of our 2nd trailer analyzer for later calibration.

17th February 2004 – Tuesday KB Noticed open connection at tee for O3 PS addition to regular O3 analyzer, which explains no response when testing new PFA gas switching valve [by adding CO cal gas to indoor sample line], ie it always sampled room air when it was operating the new valve, since restriction through that port less than via the hi-flow sample line. This must have happened when putting in old O3 analyzer for comparison. Late eve, decide to replumb continuous gas sample line, so that only acquire outdoor air from now on. TEOM still switching every half our in-/out-doors. Connecting old TEI O3 analyzer signal in place of PM_ERR signal: this is channel 7 on the Labjack terminal block [phoned with Wes]. Thumbwheel settings are 609 (span) and 53 (offset), running side by side [via manifold] with reg O3 analyzer. Create new graph “O3 comparison” with converted signal (Vdc * 100) of “Old O3” blue trace with O3 brown. Since default sample air is outdoors, I also learned how to turn off sequences individually, so that digital signals correspond to actual [continuous] outdoors gas sampling. This is a handy feature letting you alter and switch sequences. Earlier today, checked TEOM bypass F to be 16.8 lpm OK!

20th February, 2004 - Friday KB, WY ~1400 turn on O3-PS for warm up. Connect O3-PS supply port via tees with both reg O3 and old O3 analyzers. Zero air to PS supplied by UHP zero air tank. Set p regulators internal to PS [and upstream of crit orif] to 20 psi, so that plenty of excess flow when both analyzers are connected at same time. 1444 set span = 600 and offset = 71 while O3-PS level 1 = 180 ppb [but too high] 1448 offset = 66 1517 O3-PS L2= 120, 21 L3= 80, 26 L4= 40, 30 zero = 0 ppbv BUT: offset too high! 1532 new offset = 53 1535 to 1612 go through var levels 180, 120, 80, 40 and 0 ppbv. Results now in good tracing of reference signal, and good correlation; furnish cal report to Greg Huey, see “OldTEIcal 040220.xls”. Brian Jackson had put together the ECC O3 sonde, and connects to O3-PS. Wire 99 kOhm resistor into terminal ports of channel 7 on Labjack [note initially TEOM Alarm], since max current output expected to be ~10 µA! But get 0.4 V when no signal produced from ECC [ie no solution no flow]. Signal pulls down to 0.02 V when solution is filled and zero air pushed through cell, but no change in signal when supplying 180 or even 400 ppb O3! Changed low range output range from 200 to 400 ppb; note to not forget to set it back to 200 ppb later, otherwise conversion to phys units incorrect! WY and BJ measure µA output with Fluke meter directly at cell signal cable, and do get indeed no signal! I had thought that may be low current across 99kohm resistor is fighting labjack impedance and we would possibly need to amplify and isolate signal [eg using an op amp and V-supply]. BJ will check with DaveTanner re op amp on Monday, but first with Boulder manufacturer re ECC signal. Replace worn out MnO2 from CO zero trap with new Carulite. ~2010 switch to outdoor air sampling [conti gas only]. 2138 connected TEOM-Alarm (PMERR) signal to Labjack’s channel 7 again. Set up oven to regenerate Carulite (MnO2, using small KF cylinder from DT; make insulation fit the end pieces, so can fit inside oven completely) at 130C in UHP ZA [am lacking regulator for N2 tank!]. We do have 2nd full ZA tank up there, though. Set rel low flow on rotameter [lower sphere on 10 marking]; gas tank p = 800 psi.

21st February, 2004 - Saturday KB ~1400 start to let oven cool down [under flow]. Refill DT and GH’s CO zero trap [1/2” tubing] with new Carulite. Fill regenerated MnO2 into 500cc PE bottle, and refill ss KF cylinder with remaining used up Carulite for regeneration in ZA [now set at 140C]. Changed low range O3 scaling back to 200 ppb, was 400 see above! Also change PMERR gain back to +-10V, which had been set to +-1V due to low V signal from ECC O3 sonde. 1455 save new DAQ Factory settings, exit and restart DAQ. 1700 ZA tank p = 700 psi, is used for low flow regeneration of MnO2 (140C). TEOM FL = 62% Check sample pressures for consistency: CO = 25.1 inHg, NOx = 28.0 inHg, O3 = 708 Torr, same for outdoor and indoor sampling. 1705 Check indoor sample for response by exhaling into tee’d end of sample line:  all CO, NOx, O3 going down immediately, OK!

1st March, 2004 - Monday KB, BJ ~1700 connect BJ’s ECC O3 sonde signal to channel #7 on Labjack replacing PMerr signal from TEOM. Seems like he got the pump back working again, and admits he might have it run “backwards” before, since he provided power to the leads that were supposed to deliver the pump signal!! He never took off the shell from the ECC housing to see that they had a molex connector labeled for the pump power input!! In the same fashion, he had assumed that the low current signal would come out at the ends of the white ribbon cable (yel/wte leads), when instead it was conditioned on the IC board already to 0-2.5 Vdc!! Response now is no change in signal to either 0 ppb or 180 ppb from PS (had warmed up in activ C scrubbed ZA flow since ~1630). He claims a couple of tools missing [ie the pliers that came with ECC). May be that’s why they activated the buzz-card readers locking mechanism to PH-level. BJ needs to leave already again at ~1730. Notice that signal gets quieter when cell kept quiet [tape it down to small rack due to lack of better place]. ECC signal now stabilized at ~1 Vdc. Let it sample ambient air from gas manifold for the next couple of days.

3rd March, 2004 - Wednesday KB ~!700 remove regulator from mt ZA tank and haul downstairs to loading dock for pick-up; email WY tank # SKK 773 (and TDT 904 on bar code tag). Connect other full ZA tank that was still up there (last one; only one more N2 tank that is ours so far). Disconnect ECC sample tube from manifold and cap off. Turn off ECC; notice that electrolyte had been used up [evaporated]. Had been putting out ~1 ±0.1 Vdc all the time. BJ needs to commit much more time to figure out what’s wrong. Otherwise, he’ll never get this thing working…

Note TEOM FL = 70 %. Very warm outside, and sometimes negative TEOM PM mass signals when sampling indoor air. Ozone shows some more pronounced differences between indoor (low) and outdoor (50s ppb). Not sure why CO spiked up when I disconnected ECC-O3 sample tubing from manifold?

11th March, 2004 - Thursday KB, WY, SL ~1400 give intro to Sara Lance, who is TA for lab class. Note first that TEOM’s amb T signal had max-out earlier this morning, indicating problems maintaining proper flow; indeed the FLOAD is at 82 %. But ok right now; may deal with bypass valve later. Will replace TEOM filter early next week (if necessary). Note, procedure is: 1. push “data stop”; 2. replace filter; 3. push “run”. Explain her pri ncipal operation of CO analyzer. Exchange MnO2 ZT material, since ZT-eff was near zero! Use freshly regenerated Carulite [out of oven]. Ask her to exchange CO and NOx inlet filters. Also noticed that NOx maxed out at 600 ppb during rush hour this morning! ~1700 change FS range of NO, NOx, and NO2 channels from 500 to 1000 ppb! Since analog output is 5 Vdc full scale, had to change the factor on the “conti gas” graph from 100 to 200 [since 5V = 1000ppb]. Noticed dip in NOx on graph; may take a while to readjust to new gain?! Have to check later. Also need to remember to save changes before stopping and restarting program next time.

2400 save, stop and restart DAQFactory remotely. Must have just missed top of hour, so it will pick up sequences at 0100.

15th March, 2004 - Monday KB 16:16 supply ZA at 1.00 Vdc (display), ie w/flow MFC cal equ = 2.0615 *1 + 0.01 = 2.051 slm. 16:22 add NO cal at 5.02 Vdc (display) = 2.03 * 5.02 – 0.02 = 10.15 sccm since [NOtank] = 10.13 ppmv, [NOnom] = 10.15/2061 * 10130 = 49.9 ppbv! 16:27 remove NO cal line from tee with ZA; wanted to get response of analyzer for possible retro-correction of data thus far. So now again only ZA. 16:33 command ZERO on API analyzer, causing both NO + NOx to 0 (ref to page 7-4 manual). 16:45 note slope offset NOx 2.278 5.0 MV (both high!) NO 2.190 0.0 MV (slope high!) Connect NO cal line to tee with ZA, ie now supplying 49.9 ppbv NO! Poor response, slowly climbing to ~15 ppb but not 50! Doesn’t give me “SPAN” option for new factor (slope), but probably maxed out there anyways. Call API, c/o Clynch, first suggests to i) check sample flow at inlet (although ~0.47 lpm displayed, but he thinks that may be leak somewhere needing parts and o-rings changed), should nominally be 0.5 lpm ±10% (measure 0.46 lpm w/BIOS, OK); then referring to section 9.1.6 “Factory Cal Procedure” suggesting ii) to check PMT hi-V supply on top of PMT assembly front left adjust potentiometers labeled “coarse” and “fine”. When supplying 50 ppb NO “Norm PMT” should display at least twice that in mV, but we see only ~23! Change poti settings old new Coarse A C Fine 9 7 (reads like hex-dec #, eg A9=19, C7=37). SH… when pulling out analyzer it unplugged from wall power at rear panel; but is back up quickly. This leaves a noticeable spike in data record (at ~17:20). ~1740: “Norm PMT” now a little over 100, OK. Perform SPAN and ZERO twice to make sure. New slope offset NOx 0.890 0.6 MV NO 0.865 -4.4 MV (low?!) ~1750 back to ambient measure mode.

16th March, 2004 - Tuesday SL, KB 12:00 Begin CO Calibration Exercise for Air Pollution Measurements Lab Course. Large spike in CO voltage due to pressurized cell; mistakenly supplied excess zero-air with vent-line plugged. 13:35 End Calibration Exercise. Return to ambient and room sampling. 14:55 Second Calibration Exercise for Air Pollution Measurements Lab Course. 16:20 End Calibration Exercise. Return to ambient and room sampling.

17th March, 2004 - Wednesday SL 14:00 Begin CO Calibration Exercise for Air Pollution Measurements Lab Course. 15:20 End Calibration Exercise. Return to ambient and room sampling.

18th March, 2004 - Thursday SL, KB 9:00 Begin CO Calibration Exercise for Air Pollution Measurements Lab Course. At some point, power may have been disrupted. The signal did not update on the monitor. 9:24 The program was terminated and restarted. Then, it was discovered that the baseline voltage had changed. zero-air now gives a 0.2 V response in the CO analyzer, whereas yesterday zero-air gave a 0.5 V response. 11:00 End Calibration Exercise. 15:20 Begin CO Calibration Exercise for Air Pol. Meas. Lab Course. 16:12 end of exercise. ~1720 KB discovers that CO inlet line was still disconnected from sample manifold tee (venting into room), CO inlet tee still connected to cal dilution system tee, and ZA was still on but venting at open tee of dilution system (since cal side was disconnected). 17:25 turned off ZA and reconnected the CO analyzer to the manifold. 17:32 re-zeroed CO analyzer [resulting in a jump up in signal], since it clearly had drifted to negative values. This resulted in a change of slope [from 0.829 to 0.769] internally as well. 17:55 rebooted DAQ-PC, so that it can start the master time control sequence [which determines the CO zeros and other valve switchings rel to abs time] 18:00 changed TEOM filter (indicated 90% Filter Load), took until ~1845 to get back (20 % FL displayed as start-out ref) 18:25 CO analyzer leak check (to see if any harm was done when it was briefly pressurized yesterday).: spl-F down to ~.06 lpm, spl-P down to ~150 Torr with inlet capped, which is OK. 18:40 CO analyzer sampled indoor air, since we disconnected the zero valve assembly in order to pull out the analyzer and look inside. 18:55 brief spike in signal due to brushing against power switch. 19:04 CO analyzer inlet reconnected to the manifold.

19th March, 2004 – Friday SL 14:20 Begin CO Calibration Exercise for Air Pol. Meas. Lab Course. 15:29 CO Cal-gas line capped at dilution tee – only zero air supplied to CO analyzer. 16:50 End Calibration Exercise. Return to automatic ambient and room sampling.

25th March, 2004 – Thursday KB Prepare 49C-PS and analyzer for lab experiment #6. 22:30 to ~12:30 perform various tests, eg pump and external/internal leak checks, intensity and balance checks between cells A and B. Those tests all pass, but some are very close. Cell B seems to perform better than A. The O3 scrubber test yields long waiting times! Providing 180 ppb O3 from PS (0.18ppm), and with Service mode on, choose intensity check, then Int A Reference Gas, have to wait >20 min to get to stable 100,730 Hz. Providing ZA next (O3-free), wait again >20 min to yield ~100,890 Hz. At p=731 Torr and cell T = 34.5 °C, getting an approximate scrubber efficiency Seff = 88 %. Doing the same for cell B, ie reading Int B Reference Gas with 101,035 Hz for 0.18 ppm and 101,200 Hz for 0 ppb (but again very long wait times!!), yielding Seff = 91 %, calc acc to Beer lambert Law, see lab handout and manual p. 5-5. 12:40 notice CO low spl flow alarm! Spl F = 480 ccm, threshold is 500. Switch in zero mode and flow immediately goes up. Found needle valve simulating zero trap resistance too close, have to open 1 and ¼ turn, in order to get balanced with zero mode, ie spl F= 770 ccm, and p = 25.8 in Hg (655 Torr).

29th March, 2004 – Monday KB, BJ, SL Prepare 49C-PS for cal, warm up under ZA flow from the activ.C cartridge. 10:40 disconnect O3 analyzer’s sample line from manifold to use as vent line. Turn on ZA supply (tank) to dilution system for CO cal. Change inlet filter of O3 analyzer. CO ~11:00 since ambient CO levels seem low, switch into zero mode and reset zero baseline [since it has been negative for most of the time lately]. No effect on offset, though, new = old = 0.080 mV, but now new slope of 0.743 (old 0.769). Set dilution system to Fza = 1.62 V, and Fcal = 4.97 V, with Fza = 2.0615 * 1.62 + .009 = 3,350 sccm Fcal= 2.0296 * 4.97 - .0197 = 10.07 sccm, With [CO]tank = 1425 ppm, [CO]nom = 1,425,000 * 10.07 / 3360 = 4271 ppb. Calibrate to that number: new slope = 0.845 (0.743 old). IGOR evaluation yields CO slope = 1141 ±6 ppb/V, i-cept = -30 ±8.8 ppb Forcing thriugh zero CO slope = 1133 ±7.5 ppb/V (r = 0.9999). 11:20 reconnect to sample manifold. O3 O3 analyzer has been in ZA since ~11:00. 11:25 rezero O3, but insignificant change in “backgrd” level. Do full 5-point cal (180, 120, 80, 40, and 0 ppbv, for retroactive correction of data. 11:54 supply again 180 ppbv and re-set span level; OLD NEW old vs new factors: Background -1.5 -1.7 High coefficient 1.025 1.102 Low coefficient 1.023 1.103 12:16 back to ambient measurement (connect to manifold). The IGOR evaluation yields slope = 21.586, i-cept = 0.26 ppbv! NOx 11:40 supply ZA 11:50 re-zero analyzer Set dilution system to Fza = 0.48 V, and Fcal = 5.02 V, with Fza = 2.0615 * 0.48 + .009 = 998.5 sccm Fcal= 2.0296 * 5.02 - .0197 = 10.17 sccm, With [NO]tank = 10.13 ppm, [NO]nom = 10,130 * 10.17 / 1009 = 102.1 ppb. Calibrate to that number; OLD NEW Offset NO = -4.4 -1.0 mV NOx = 0.6 7.3 mV Slope NO = 0.865 0.550 NOx = 0.890 0.558 (may consider lowering the internal gain!!) IGOR evaluation yields NO slope = 116.18, NO i-cept = 0.97 (r= 0.9998); NOx slope= 107.75, NOx i-cept= 0.93 (r=0.9999) 12:14 back to ambient measurement (re-connect to manifold). 12:40 remove CO zero trap and exchange exhausted MnO2 with newly regenerated. Start regeneration of used up pellets in ZA at 150 °C. ECC-O3 ~12:30 connect ECC-O3 signal to daq system channel 7, and suply now 240 ppbv (from 500), get ~1.5 Vdc signal response. 12:53 set PS to supply 180 ppbv  ~1.2 Vdc; 13:10 set PS to supply 120 ppbv  ~0.8 Vdc; 13:16 set PS to supply 500 ppbv  ~3.3 Vdc, and leave. 14:47 disconnect PS and shut off; connect ECC spl line to manifold to sample ambient air.

7th April, 2004 – Wednesday KB, lab class, Dave, Sean, Kelly, Andrea Calibrate NO/NOx analyzer with D & S [get David’s notes]. Help check TEOM with K & A: ~1520 disconnect TEOM inlet line from branch that connects to the indoor cyclone head; cap broken ends, and have them do flow audit with single line to outdoor inlet. WE SAMPLE FROM NOW ON ONLY OUTDOOR AIR! Need to de-activate the PM in/out valve switching, since it’s still being recorded. ~1730 noticed that ECC sonde was disconnected from its sample line, which was NOT CAPPED, ie we were pulling in room air into the manifold back through that line!! Need to find out from BJ when he did that!? Exchange manifold gas inlet screen with clean one; old one fairly dirty, goes into sonic bath. TEOM FL = 48 %. K & A need to come back tomorrow for K0 verification, using pre-weighed filter in cal package [weight = 0.083305 g or so].

8th April, 2004 – Thursday KB, lab class, Burcak & Farhan Calibrate CO but w/out actually resetting internal gain and offset of analyzer. ~1420 LT supply ZA to inlet, excess venting into room go through sequence of COza, CO0 (ZA in zero mode), CO0+span1, span1, 2, 3, COza. ~1530 LT done, reconnect to manifold for ambient air sampling. 1658 stop and start DAQ factory, and stop PM and gas in/out switching, ie both gas and pm2.5 sampling outdoors only from now on! Also, DAQ Factory recording time now switched to LT [had been EST until stop]. Kelly & Andrea didn’t show, not sure what status TEOM is in [looks as if sampling outdoor air]. At 1730 LT activate CO zero manually, since I missed activating the master time control to activate the CO zero automation. ~2100 TEOM FL = 51 %.

13th April, 2004 – Tuesday KB 2355 LT reconnect the TEOM indoor lines. Stop start DAQ and initiate master control to activate automated CO zero and indoor/outdoor switching of gases and TEOM. FL = 31%.

15th April, 2004 – Thursday KB, BJ Brian needs to record also pump temperature of the ECC O3 sonde in order to determine accurate ozone mixing ratio. Hook up ECC pump T signal (white wire) to DAQ FAct ch 2 (replacing “AmbT” temporarily). The actual ECC O3-signal was and remains connected to ch 7 (acquired as “PMERR”). Perform another calibration of the TEI O3 analyzer (49C UV absorption) since we noticed that it is well below the nominal 180 ppbv we are supplying with the 49C-PS. ~1530 supply 180 ppbv and re-set span level; OLD NEW old vs new factors: Background -1.7 0.5 High (FS 400 ppbv) coefficient 1.102 1.208 Low (FS 200 ppbv) coefficient 1.103 1.208

15:43, hooked ECC into ozone standard 15:47, switched to zero air 15:51, switched to 180ppb

!6:50, reconnected TEI analyzer and ECC to ambient air.

21st April, 2004 – Wednesday KB 20:25 exchange CO zero trap (MnO2), now with first holder filled with Drierite silica gel and second (downstream) holder with MnO2. put back in line just before zero mode [see spike]. Adjust flow [750 ccm] and p [25.3 in Hg] for sample mode with needle valve.

26th April, 2004 – Monday KB 16:45 LT exchange back signal cable connections of PMERR (DAQ ch 7) and AmbT (DAQ ch 2), which had been used for Brian Jackson’s ECC O3 experiment (O3 sig and ECC pump T, resp), who appears to be done with his measurements. 1655 LT stop and restart DAQ Factory “ES&Tpenthouse”.

20th May, 2004 – Thursday KB ~1300 check TEOM bypass flow: way too low!! With that notice that in-/outdoor gas sampling is out of balance as well. Use CO, Nox and O3 pressure readings to set for approx constant sample pressures in both modes [compromise with flow rate in outdoor mode not too low!]. Set TEOM bypass flow to 16.7 lpm [~80 mark on rotameter]. Now indoor mass significantly lower than outdoor, ie slightly negative. Will have to test with head outside to see if it is a moisture/temperature effect, since the indoor air is much cooler and [possibly] dryer than outside air, which may have an effect on TEOM filter, esp if Naphion dryer not 100 % efficient.

24th May, 2004 – Monday KB ~2000 first take down indoor cyclone and position next to wall port through which all tubing is passed to outside; at ~2100 take indoor cyclone outdoors and mount it to perforated angle bracket near outside wall.

28th May, 2004 – Friday KB ~1515 turn off TEOM switching while it is in outdoor sampling mode (non-energized solenoid), disconnect indoor plumbing from outdoor sample lines and cap off broken ends at TEOM sampling side. Let pump maintain flow through this (3rd) port, although now not connected. THIS WILL SHOW IF TEOM SENSITIVE TO DIFFERENT SAMPLE AIR PRESSURES, since bypass flow of additional 16.7 lpm now disconnected from inlet Tee. The abrupt change to higher pressure [less vacuum] causes positive artifact, ie signal goes up, but comes down within half hour.

30th May, 2004 – Sunday KB ~1615 start working on running TEOM indoor sample line to return duct in ceiling of lab interior [in front of fume hood on north side]. 1730 connect bypass flow to Tee of outdoor sample line: abrupt decrease in sample pressure now causes the TEOM signal to decrease, but is coming back up to about same value as before within half hour. SUDDEN DECREASE IN SAMPLE PRESSURE CAUSES TEOM SIGNAL TO DECREASE BUT RECOVERS WITHIN HALF HOUR. Run sample line for gas-phase indoor sampling to same return duct in ceiling. 1759 stop and start program to activate indoor/outdoor switching again as usual, i.e. start 15 min cycling of in/out gas-phase sampling with indoor air first, and start 30 min TEOM cycling with outdoor air first at top of the hour (1800). Still largely negative signal for indoor air, which is likely much dryer than outdoor air, hence dry indoor air dries off moisture from TEOM filter that was previously collected with outdoor particles. OUR NAPHION DRYER MUST BE FAIRLY INEFFICIENT!! Adjust the NV in the bypass of the Nafion sheath flow to maximize flow through the Nafion sheath, counter flowing against the sample flow [ie from bottom up]; closing NV ~ 1 full turn until sample flow starts to deviate [decrease] from nominal 3 lpm. Telecon with Mike B to ask if can borrow drier cartridge. He oks and I replace their used up one in their Neph-PSAP setup upstream of cow- utter with a regenerated one. I dump the used up Drierite with new one from our stock. 2025 I plum Drierite cartridge downstream of Tee and upstream of the Nafion dryer counter sheath flow inlet at bottom of the dryer.

1st June, 2004 – Tuesday KB ~1530 start re-plumbing TEOM so that counter sheath flow through Nafion dryer is provided by separate pump and NOT integrated in exhaust of TEOM pump. Use critical orifice labeled 21 lpm from RW stash, and insert at a new Tee at C-vane pump inlet [now 4 legs splitting off]. The flow results in ~20 lpm when installed. Run 3/8 line over to TEOM {~18 “) and connect directly at top outlet of Nafion dryer. Bottom inlet directly connected to Drierite cartridge. This adds restriction [esp Nafion dryer] so that flow through dryer cartridge [measured at inlet sampling indoor air] now is ~12 lpm. The work disturbed system quite a bit; done by ~1700, oscillations quiet down by ~1800. TEOM FL = 77 %.

3rd June, 2004 – Thursday KB ~1835 change TEOM Nafion dryer plumbing and flow rate: put in metering valve at outlet side of dryer and take critical orifice out near the pump side. Set flow rate down from ~20 lpm to ~8 lpm with one of our Drierite cartridges installed. Will ask Laura K to regenerate Drierite and refill MB’s cartridge. ~1845 quick check of TEOM bypass flow (14 lpm) seting it back up to 16.7 lpm. This causes a brief excursion of TEOM signal to negative values being in indoor sampling mode at the time. Also exchange gas sample inlet screen on platform outside; clean under running water [not very dirty this time] and sonicate in DDW for ~1 hr. TEOM FL= 79 %.

8th June, 2004 – Tuesday KB ~2210 Change CO zero trap Drierite and MnO2, and adjust flow rate; NV has to be fully open in order to equal flow and pressure in zero mode, which was not the case before.?. ~2225 change Drierite in TEOM Nafion dryer sheath flow cartridge and check flow rate: ~8 lpm OK. Must have experienced significant pressure change, since signal goes way down (-100), and takes more than an hour to come back up. May be I should put the sheath flow metering valve UPSTREAM of the Nafion dryer?? TEOM FL indicating 89%; will change when back from Aerodyne.

11th June, 2004 – Friday KB 2000 stop TEOM switching, remain in outdoor mode. Break and cap off Tee for indoor line. TEOM FL was 88 % but had riggered alarm earlier, so change filter; new FL=21 %. Also change bypass inline filter and Drierite cartridge for Nafion sheath flow. Notice when leaving bldg later that night (~2130), that baseball game and/or other sports event ongoing outside to east, with RVs parked along curb and idling engines. Air is extremely hazy, as seen esp in the scattered flood lights around field.

14th June, 2004 – Monday KB 1340 exchange Drierite cartridge for Nafion sheath flow, which causes TEOM signal to drop out briefly probably due to pressure change. Collect new SCC that came in from R&P from Rodney. Ask Laura king to clean PM 10 head that was sitting in main lab and will go with new SCC later on upstairs, replacing corroded inlet of first generation kind. Start regenerating MnO2 carulite in oven upstairs with ZA from tank; set at 180 deg C and low flow rate, ie top ball at ~10 of rotameter scale. Noticed CO zero trap is exhausted, but forgot my access card today; will have to be done next time. Show Gayle how to download data from DAQ Factory; will have to email her the Igor macro for converting the signals.

15th June 2004 - Tuesday WY 1515: Per KB’s remote request I turn off the oven heat for the carbon denuder regeneration. 1610: Zero air flow to carbon denuder closed off.

18th June 2004 - Friday KB ~1100 visit lab touring Kevin Dunn from CDC, who is interested in borrowing our ECC sonde for a human exposure study focusing on athletes later this summer. We can’t find the manual; will have to contact Walt Komhyr from EnSci Corp in Boulder.

~1800 noticed that we must have had a power glitch earlier today (~1300), since PC was off; reboot and start DAQ Factory program. Noticed also wire for TEOM switching disconnected from DAQ signal terminal block (ch I/O 2); reconnect, but then miss to stop TEOM switching, so as it tries to go in indoor mode, it has to work against bypass pump from TEOM setup [where ends to indoor cyclone were capped], causing large negative and positive excursions! This was partly caused also by refilling Drierite in cartridge of TEOM Nafion drier sheath flow.

Take MnO2 pellets for CO zero trap out of oven, where they had been regenerated the eve before. Refill zero trap also with Drierite in upstream holder. Change all inlet Teflon filters (O3, NOx, CO); noticed the one in O3 analyzer had been ruptured!! CHECK CELLS FOR DIRT NEXT TIME!! Noticed low flow alarm in O3 analyzer when sampling outdoor air: found ½” Teflon tubing kinked at point where it is attached to rack. Don’t know for how long it has been kinked, but it seems to explain the large differences in [O3] we saw recently with indoor levels being HIGHER!! Install strain relief for sample line bundle from ceiling behind rack. Low flow alarm gone but O3 sample flows through cells A and B are close to lower threshold; may need to replace pump membrane soon. KEEP EYES ON O3 SAMPLE PUMP.

22nd June 2004 - Tuesday KB ~1000 try to connect remotely but no luck. Call Amy to reboot PC due to possible power outage. We had intense T-storms last eve, which might have caused this. Start collecting data again at 1100; turn off TEOM in/out switching sequence so that we sample only outdoor air again.

24th June 2004 - Thursday KB ~1830 replace TEOM inlet which was a CrO2 plated 1st generation SCC and corroded inseparably with the upper PM10 head, with new SCC out of Al and PM10 head from partisol (?). Tapped screw holes had to be drilled into new SCC in order to mount it properly in place. Also noticed that CO ZT (MnO2) is becoming unefficient, so exchange the tandem Drierite- MnO2 filters. New drierite also in TEOM’s Nafion drier sheath flow. Noticed that flow A in O3 is calling Alarm being just below threshold of 400 ccm, but have to run. ~1900 fill SS tube with used MnO2 and start regeneration in tube furnace at 180 C in small ZA flow.

25th June 2004 - Friday LK per KB request ~1230 turn off tube furnace heat (was 180 C), ZA flow remains on until later. ZA was fogotten to be turned off until Saturday 2300!

1st July 2004 - Thursday WY 1255: Shut down O3 to find source of low flow alarm on both channels. Find ruptured pump diaphragm, replace, and restart at 1315. Initial data is noisy, but I think it will quiet down soon. ~1650 LK per KB request exchanges drierite for nafion sheath flow on TEOM.

12th July 2004 - Monday KB, LK 1625 check difference in sample pressures between indoor and outdoor at inlets of NOx and CO analyzers; adjust flows at main flow rotameters slightly. Exchange bug screen elbow fitting at manifold inlet of outdoor sample line. Retrieve regenerated MnO2 pellets that had been left in SS cartridge inside oven. Measure flows of PCM C (LK pls check, it’s the old gen PCM), that had been used last week for C-monolith DBT runs. Channel labels from inside pump box [corresp to labels outside inlet box]: ch # amb lpm slm “Hg vacuum 1 19 2 19 3 18.5 Start regeneration of C-monolith “C”, which had been used last during the DBT and smoke sampling at Ft Benning prior to that. Set oven at 180 °C and low flow of UP zero air [top ball at ~15 mark] passing over (KMnO4 + Activated Charcoal)-trap. Note: ZA tank is close to empty! Need to keep an eye on flow and cylinder pressure in the morning!!

29th July 2004 - Tuesday KB ~1600 change response time on new API CO 300EU analyzer [received from Greg Braswell and Bill Turner on Thursday last week]: >Setup  Pass-code 929  More  VARS  jump to “010”, which gets one directly to “FILT_SIZE= xxx samples”. Sampling rate is 3 Hz, and xxx was set to 750, set now to 180, ie The analyzer will approx keep a running 1 min average (180/3=60s). If 180 is too noisy, go back up, if too slow go further down. Notice flow alarms in sample mode for both analyzers now: swap out NV with a less restrictive one; zero mode [ie flow through ZT] seems to be ok. ~1900 switch manual zero for both analyzers [had plumbed it Thursday with tee downstream from C-port of ZV, so that both get fed with zero air out of MnO2 trap simultaneously]. New analyzer has negative offset [~-330 ppb], in 3rd min set it to zero! Since we are out of UHP zero air, calibration has to wait. 2010: changed FILT_SIZE value to 360, since it seemed to be too noisy. TEOM FL= 80%. for calibration of new CO analyzer (API 300EU). First exchange MnO2 and Drierite in zero trap holder. Second, check both [old and new] analyzers’ sample flow rates and pressures:

Time Spl mode Analyzer P (inHg) F (ccm) 1528 Outdoor new 23.4 ~1460 (fluctuating) old 23.1 ~670 (“) 1531 Zero new 23.6 ~1490 old 23.3 ~673 1535 Indoor new 23.4 ~1450 old 23.1 ~660 System seems well balanced!

1547 provide ZA from new ZA tank [Airgas’ ultra-zero, arrived today]. Check validity of ZA-MFC equation used during class earlier this spring: Fza (slm) = 2.0615 * Uza (Vdc) + 0.0093 Eq. (1) Where Vdc is from display of MFC control and dilution unit. Set Uza = 1.20 Vdc and measure w/BIOS = 2,545 sccm, vs Eq.1 = 2,483 sccm, ie 2% less; OK!!

Check validity of CO cal MFM equation used during class earlier this spring: Fco (sccm) = 2.0296 * Uco (Vdc) - 0.0197 Eq. (2)

Set Uco = 5.15 Vdc and measure w/BIOS = 10.79 sccm, vs Eq.2 = 10.43 sccm, ie 3% less; OK!!

Since CO tank conc = 1425 ppm. [CO]nom = 1425*10.79/(2545+10.8) = 6,016 ppb  TOO HIGH!!

Since already plumbed, dial down CO cal MFM to Uco = 3.92 V corresp Fco = 7.94 sccm (eq.2), BIOS = 8.12 sccm, hence new [CO]nom = 1425*8.1/(1425+8.1) = 4,521 ppb. Will connect CO cal line to dilution tee when ready (see below at 1611). Time Mode Action Uco (Vdc) BIOS corr Fco [CO]nom supply Start end sccm 1547 ZA-meas ZA to inlet n/a n/a n/a CO of ZA-tank 1607 ZA-zero ZV on n/a n/a n/a 0 1611 Cal-zero connect cal 3.92 ? 8.12 (4532 ppb)  ZT eff. 1615 Cal-meas ZV off 3.92 3.99 8.12 - 8.27 4532 - 4613 ppb 1619 Cal-meas Change Uco 2.32 2.36 4.80 – 4.88 2681 – 2727 ppb 1624 Cal-meas Change Uco 0.93 0.96 1.91 – 1.97 1069 – 1104 ppb 1629 ZA-meas shut-off Fco n/a n/a n/a CO of ZA-tank 1630 ZA-zero ZV on n/a n/a n/a 0 Actively “zero” both analyzers!! 1634 Cal-zero turn-on Fco average 3.91 avg 8.1 (~ 4521 ppb)  ZT-eff. 1635 Cal-meas ZV off average 3.91 avg 8.1 ~ 4521 ppb

During next 10-15 min calibrate both analyzers by actively setting span to 4521. Comparison of previous and post cal settings of slope and offset. 1655 back to regular ambient measure mode. Offset Slope Pre-cal post-cal pre-cal post-cal New CO 0.04996 0.04996 1.110 1.045 Old CO 0.080 0.079 0.845 0.898

BUT: old CO reads now mostly negative, so 1720 to 1730 re-zero old analyzer only to post-cal Offset = 0.080, changed also slope to now 0.837!!

Since ca 1700 regenerate used-up MnO2 (Carulite) at 180 C with new ZA.

TEOM-FL = 82%. Don’t touch plumbing yet, LK just exchanged Drierite for Nafion sheath flow this morning.

3rd August 2004 - Tuesday KB, LK, Kevin Dunn (CDC) Temporarily connect ECC-O3 signal (yel=com; red=Vdc) in place of new CO signal (labeled TEOM-ERR in DAQ). Had turned on O3-PS earlier for warm-up, and plumbed both fix- installed TEI O3 analyzer and ECC-O3 analyzer incl. external Tee for PS-vent. The nominal O3 concentrations were switched as follows. 1300 LT 120ppb 1311 80 1313 40 1316 0 Disconnected at 13:19 Old calibration factors for O3: 1.2 (for both low and high ranges) 1322 180ppb 1325 0 zero TEI analyzer! 1326 180 1330 120 1332 80 cal O3 analyzer (since typical MR level) 1336 40 1341 0 1346 reconnected to ambient air. New TEI-O3 cal factors: High range = 0.975, Low range = 0.976 (acquired)!

2020 change CO zero trap’s MnO2 catalyst and Drierite; notice flow alarm on new CO analyzer; in deed the NV bypassing the ZT had been too restrictive: open up again. Take opportunity to adjust main sample indoor/outdoor flows to read equal pressures and flow rates in analyzers tapping off the manifold. Eg new CO spl p = 24.0 inHg, spl F ~ 1500 ccm old CO spl p = 23.7 inHg, spl F ~ 670 ccm, OK.

Retrieve MnO2 pellets that regenerated in oven over weekend. TEOM FL = 85 %.

6th August 2004 - Friday KB LK remotely via phone instructions exchanges TEOM filter, since FL>90 %. Procedure: 1. push “data stop”; 2. replace filter; 3. push “run”. KB later detects remotely that TEOM would not reach normal operation mode, ie values remain negative; KB visits lab late night. Noticed no specific “Alarm” detected by TEOM. The operation mode indicated 4+, all temperatures and flows were at nominal set-points, but Noise level was zero: opened sensor block after “data stop”, and re-pushed filter cartridge onto glass stem. Noticed dust particles in/around filter cavity of block and rubber seal, which were cleaned off. Closed block and tightened screw. Wiggled connectors at both sensor and control units. Power-cycled system, and used re-start initialization to re-plumb sample lines as follows:

PM Spl 2.5 16.7 lpm

Pump Flow Splitter 13.7 lpm Aux F 3 lpm Main F

Nafion Dryer Needle Valve

Sensor Unit

Control Unit

Fig.: The NV serves to adjust flow through Nafion Dryer, which otherwise would be too restrictive and itself act like a critical orifice reducing the total sample flow to << 16.7 lpm. 10th August 2004 - Wednesday KB ~1315 re-plumb TEOM to incorporate indoor/outdoor sampling, i.e. use manifold flow (C-vane) pump set at 16.7 lpm and tee off upstream of TEOM flow splitter inlet (see above Fig.) to provide valve-controlled bypass flow to either indoor or outdoor sample line, and let TEOM sample the respective other line at the same time. Exchange CO zero trap MnO2 pellets and Drierite just before the next CO zero mode (at 1330), and adjust flow rates for all 3 modes (zero, in-, out-door) to be at same pressure. Don’t turn on TEOM in/out-door switching yet, to see if opening bypass port had any effect.

I noticed a rapid drop in NO, NOx and CO earlier today, shortly after 0830. Not sure if real (e.g. rapid shift in winds and air mass flow) since we don’t measure met, or what else happened. All instruments seem to work fine, and no alarms are present anywhere!

17th August 2004 - Tuesday KB ~2215 check on CO ZT and notice that NV had been too restrictive for CO meas mode: less than 100 ccm flow through each CO analyzer. Open NV and old CO drops down [which had been recording noisier and higher than the new CO]. Exchange MnO2 zero trap pellets and Drierite, and install again. Check spl pressures and adjust flows via NV setting. Rename DAQ sequences and try to rename digital (valve) channels also to something more plausible but have to give up playing around. TEOM FL= 39%.

20th August 2004 - Friday KB ~1820 check on main spl flows and pressures in analyzers for different modes; slight adjustments required. Also increase TEOM bypass flow slightly, since it seemed to have dropped a bit below the nominal 16.7 lpm. Heavy T-storm is rolling in. EAS and CEE potluck parties are ongoing this today since 1600.

24th August 2004 - Tuesday KB ~1920 (?) start regeneration of MnO2 in ZA at 180 C. Amy will turn off for me in the morning. We should ideally use N2 for this, but don’t have a regulator with a CGA580 fitting required for the N2 tank. Amy’s group apparently has a spare which I can borrow next time!

26th August 2004 - Thursday KB ~1720 disconnect the new CO signal from DAQ, and pack up for pick-up by Greg Braswell (Teledyne-API) later next week. Reconnect TEOM Alarm signal to this AI channel 7. Instruct Laura K how to do the ECC O3 cal with CDC’s Kevin Dunn next week, when I’ll be gone. Retrieve regenerated MnO2 and store in labeled PE bottle. Exchange Drierite in the CO zero trap combo; current MnO2 still effective. Clean inlet screen of gas sample line and adjust flows between indoor and outdoor sampling, and zero mode. CO now set at 16.3 inHg spl P and ~700 ccm spl flow rate.

2nd September 2004 - Thursday KB remote from IVD 9/7/04 Potential power outage due to electrical work in 4305 lab (per 9/1 email from G. Zhu).