Rule 1007. The alternate version of procedure L is as follows: 1. Introduction. 1.1 Applicability. This procedure is applicable for determining the input of volatile organic compounds (voc), measured as equivalent propane as measured by a flame ionization instrument. It is intended to be used as a segment in the development of liquid/gas protocols for determining voc capture efficiency (ce) for surface coating and printing operations.1.2 Principle. The amount of voc introduced to the process (l) is the sum of products of the weight (w) of each voc containing liquid (ink, paint, solvent, or similar material) used and its voc content (v), corrected for a response factor (rf) to allow the input to be calculated in terms of propane, the same calibration gas used in the gaseous voc measurements. A sample of each coating used is distilled to separate the voc fraction. The distillate is used to prepare a known standard for analysis by a flame ionization analyzer (fia), calibrated against propane, to determine its rf. 2. Apparatus and reagents. 2.1 Liquid weight. 2.1.1 Balances/digital scales. To weigh drums of voc containing liquids to within 0.2 lb.2.1.2 Volume measurement apparatus (alternative). Volume meters, flow meters, density measurement equipment, or similar material, as needed to achieve the same accuracy as direct weight measurements.2.2 Response factor (rf) determination (fia technique). The voc distillation and tedlar gas bag generation systems apparatus are shown in figures 1 and 2. The following equipment is required:2.2.1 Sample collection can. An appropriately sized metal can to collect voc-containing materials. The can shall be constructed in such a way that it can be grounded to the coating container.2.2.2 Needle valves. To control gas flow.2.2.3 Regulators. For fia, calibration, dilution, and sweep gas cylinders.2.2.4 Tubing and fittings. Teflon and stainless steel tubing and fittings with diameters and lengths and sizes determined by connection requirements of the equipment.2.2.5 Thermometer. Capable of measuring the temperature of the hot water and oil baths to within 1 degree Celsius.2.2.6 Analytical balance. To measure plus or minus 0.01 mg.2.2.7 Microliter syringe. 10-microliter size.2.2.8 Vacuum and pressure manometers. 0 to 760 mm (0 to 30 in.) hg.U-tube manometer, vacuum or pressure.2.2.9 Hot oil bath, with stirring hot plate. Capable of heating and maintaining a distillation vessel at 110 plus or minus 3 degrees Celsius.2.2.10 Vacuum/water aspirator. A device capable of drawing a vacuum to within 20 mm hg from absolute.2.2.11 Rotary evaporator system. Complete with folded inner coil, vertical style condenser, rotary speed control, and teflon sweep gas delivery tube with valved inlet. Buchi rotavapor or equivalent.2.2.12 Ethylene glycol cooling/circulating bath. Capable of maintaining the condenser coil fluid at minus 10 degrees Celsius.2.2.13 Dry gas meter. For the precise measurement of dilution gas volume. It shall be calibrated to a primary standard, either spirometer or bubble meter.2.2.14 Activated charcoal/mole sieve trap. To remove any trace level of organics picked up from the dry gas meter.2.2.15 Gas coil heater. Sufficient length of 0.125-inch stainless steel tubing to allow heating of the dilution gas to near the water bath temperature before entering the volatilization vessel.2.2.16 Water bath, with stirring hot plate. Capable of heating and maintaining a volatilization vessel and coil heater at a temperature of 100 plus or minus 5 degrees Celsius.2.2.17 Volatilization vessel. 50-milliliter midget impinger fitted with a septum top and loosely filled with glass wool to increase volatilization surface.2.2.18 Tedlar gas bag. Capable of holding 30 liters of gas, flushed clean with zero air, leak tested and evacuated.2.2.19 Cylinder of compressed zero air. Used to supply dilution air for making the tedlar bag gas samples.2.2.20 Cylinder of compressed thc free N2. Used as sweep gas in the rotary evaporator system.2.2.21 Organic concentration analyzer. An fia with a span value of 1.5 times the expected concentration as propane; however, other span values may be used if it can be demonstrated that they would provide more accurate measurements. The fia instrument shall be the same instrument used in the gaseous analyses adjusted with the same fuel, combustion air, and sample backpressure (flowrate) settings. The system shall be capable of meeting or exceeding the following specifications:2.2.21.1 Zero drift. Less than plus or minus 3.0% of the span value.2.2.21.2 Calibration drift. Less than plus or minus 3.0% of span value.2.2.21.3 Calibration error. Less than plus or minus 5.0% of the calibration gas value.2.2.22 Integrator/data acquisition system. An analog or digital device or computerized data acquisition system used to integrate the fia response or compute the average response and record measurement data. The minimum data sampling frequency for computing average or integrated values is 1 measurement value every 5 seconds. The device shall be capable of recording average values at least once per minute.2.2.23 Chart recorder (optional). A chart recorder or similar device is recommended to provide a continuous analog display of the measurement results during the liquid sample analysis.2.2.24 Calibration and other gases. For calibration, fuel, and combustion air, if required, contained in compressed gas cylinders. All calibration gases shall be traceable to NIST standards and shall be certified by the manufacturer to plus or minus 1% of the tag value.Additionally, the manufacturer of the cylinder should provide a recommended shelf life for each calibration gas cylinder over which the concentration does not change more than plus or minus 2% from the certified value. For calibration gas values that are not generally available, alternative methods for preparing calibration gas mixtures, such as dilution systems, may be used with prior approval. 2.2.24.1 Fuel. 99.995% hydrogen, 40% hydrogen/60% helium, or 40% hydrogen/60% nitrogen. The fia manufacturer's recommended fuel shall be used. An attempt shall be made to avoid fuels with oxygen to avoid an oxygen synergism effect that reportedly occurs when oxygen concentration varies significantly from a mean value.2.2.24.2 Carrier gas. High purity air with less than 1 ppm of organic material (as propane) or less than 0.1% of the span value, whichever is greater.2.2.24.3 Fia linearity calibration gases. Low-, mid-, and high-range gas mixture standards with a nominal propane concentration of 20 to 30, 45 to 55, and 70 to 80% of the span value in air, respectively. Other calibration values and other span values may be used if it can be shown that more accurate measurements would be achieved.2.2.24.4 System calibration gas. Gas mixture standard which contains propane in air and which approximates the voc concentration expected for the tedlar gas bag samples. 3. Determination of liquid input weight. A capture efficiency test shall consist of not less than 3 sampling runs. Each run shall cover at least 1 complete production or processing cycle or shall be at least 1 hour in duration. For automotive surface coating operations, the sampling time per run shall be based on coating a minimum of 3 representative vehicles. 3.1 Weight difference. Determine the amount of material introduced to the process as the weight difference of the feed material before and after each sampling run. In determining the total voc-containing liquid usage, account for all of the following: (a) The initial (beginning) voc-containing liquid mixture.(b) Any solvent added during the test run.(c) Any coating added during the test run.(d) Any residual voc-containing liquid mixture remaining at the end of the sample run. 3.1.1 Identify all points where voc-containing liquids are introduced to the process. To obtain an accurate measurement of voc-containing liquids, start with an empty fountain, if applicable. After completing the run, drain the liquid in the fountain back into the liquid drum, if possible, and weigh the drum again. Weigh the voc-containing liquids to plus or minus 0.5% of the total weight (full) or plus or minus 0.1% of the total weight of voc-containing liquid used during the sample run, whichever is less. If the residual liquid cannot be returned to the drum, drain the fountain into a preweighed empty drum to determine the final weight of the liquid.3.1.2 If it is not possible to measure a single representative mixture, then weigh the various components separately, for example, if solvent is added during the sampling run, weigh the solvent before it is added to the mixture. If a fresh drum of voc-containing liquid is needed during the run, then weigh both the empty drum and the fresh drum.3.2 Volume measurement (alternative). If direct weight measurements are not feasible, the tester may use volume meters, flow rate meters, and density measurements to determine the weight of liquids that are used if it can be demonstrated that the technique produces results equivalent to the direct weight measurements. If a single representative mixture cannot be measured, measure the components separately. 4. Determination of voc content in input liquids.4.1 Collection of liquid samples.4.1.1 Collect a 1-pint or larger sample of the voc-containing liquid mixture at each application location at the beginning and end of each test run. A separate sample shall be taken of each voc-containing liquid that is added to the application mixture during the test run. If a fresh drum is needed during the sampling run, then obtain a sample from the fresh drum.4.1.2 When collecting the sample, ground the sample container to the coating drum. Fill the sample container as close to the rim as possible to minimize the amount of headspace.4.1.3 After the sample is collected, seal the container so the sample cannot leak out or evaporate.4.1.4 Label the container to identify clearly the contents.4.2 Distillation of voc. 4.2.1 Assemble the rotary evaporator as shown in figure 1.4.2.2 Leak check the rotary evaporation system by aspirating a vacuum of approximately 20 mm hg from absolute. Close up the system and monitor the vacuum for approximately 1 minute. If the vacuum falls more than 125 mm hg in 1 minute, repair leaks and repeat.4.2.3 Deposit approximately 20 mls of the sample (inks, paints, or similar material) into the rotary evaporation distillation vessel.4.2.4 Turn off the aspirator and gradually apply a vacuum to the evaporator of within 20 mm hg.4.2.5 Begin heating the vessel at a rate of 2 to 3 degrees Centigrade per minute, maintaining the vacuum specified in 4.2.3. Care shall be taken to prevent material bumping from the distillation flask.4.2.6 Continue heating until a temperature of 110 degrees Centigrade is achieved and maintain this temperature for not less than 10 minutes or until the sample has dried in the distillation flask.4.2.7 Slowly introduce the N2 sweep gas through the purge tube and into the distillation flask, taking care to maintain not less than 125 mm hg vacuum at all times.4.2.8 Continue sweeping the remaining solvent voc from the distillation flask and condenser assembly for 10 minutes or until all traces of condensed solvent are gone from the vessel and the still head.4.2.9 Disassemble the apparatus and transfer the distillate to a labeled sealed vial. 4.3 Preparation of voc standard bag sample. 4.3.1 Assemble the bag sample generation system as shown in figure 2 and bring the water bath up to a near-boiling temperature.4.3.2 Inflate the tedlar bag and perform a leak check on the bag.4.3.3 Evacuate the bag and close the bag inlet valve.4.3.4 Record the current barometric pressure.4.3.5 Record the starting reading on the dry gas meter, open the bag inlet valve, and start the dilution zero air flowing into the tedlar bag at approximately 2 liters per minute.4.3.6 The bag sample voc concentration shall be similar to the gaseous voc concentration measured in the exhaust gas ducts. The amount of liquid voc required can be approximated using the equations in section 6, the gaseous voc measurement results in terms of propane, and an assumed response factor of 1.0. Let Cc3 equal the exhaust gas concentration in terms of propane and rf=1.0. Calculate Cvoc. Let bv = 20 liters and calculate ml, the approximate quantity of liquid to be used to prepare the bag gas sample.4.3.7 Quickly withdraw an aliquot (approximately 5 microliters) of sample from the distillate vial with the microliter syringe and record its weight from the analytical balance to the nearest 0.01 mg.4.3.8 Inject the contents of the syringe through the septum of the volatilization vessel into the glass wool inside the vessel.4.3.9 Reweigh and record the tare weight of the now empty syringe.4.3.10 Record the pressure and temperature of the dilution gas as it is passed through the dry gas meter, as shown in the figure 2 diagram.4.3.11 After approximately 20 liters of dilution gas have passed into the tedlar bag, close the valve to the dilution air source and record the exact final reading on the dry gas meter.4.3.12 The gas bag is then analyzed by fia within 1 hour of bag preparation in accordance with the procedures contained in section 4.4.4.4 Determination of voc response factor.4.4.1 Start up the fia instrument using the same settings as used for the gaseous voc measurements.4.4.2 Perform the fia analyzer calibration and linearity checks according to the procedure in section 5.1. Record the responses to each of the calibration gases and the back-pressure setting of the fia.4.4.3 Connect the tedlar bag sample to the fia sample inlet and record the bag concentration in terms of propane. Continue the analysis until a steady reading is obtained for not less than 30 seconds. Record the final reading and proceed with the calculation of the response factor.4.5 Determination of coating voc content as voc (vu).4.5.1 Determine the voc content of the coatings used in the process using EPA method 24 or 24a as applicable. 5. Calibration and quality assurance. 5.1 Fia calibration and linearity check. Make necessary adjustments to the air and fuel supplies for the fia and ignite the burner. Allow the fia to warm up for the period recommended by the manufacturer. Inject a calibration gas into the measurement system and adjust the back-pressure regulator to the value required to achieve the flow rates specified by the manufacturer. Inject the zero- and the high-range calibration gases and adjust the analyzer calibration to provide the proper responses. Inject the low and mid-range gases and record the responses of the measurement system. The calibration and linearity of the system are acceptable if the responses for all 4 gases are within 5% of the respective gas values. If the performance of the system is not acceptable, repair or adjust the system and repeat the linearity check. Conduct a calibration and linearity check after assembling the analysis system and after a major change is made to the system. A calibration curve consisting of zero gas and 2 calibration levelsshall be performed at the beginning and end of each batch of samples.5.2 Systems drift checks. After each sample, repeat the system calibration checks in section 5.1 before any adjustments to the fia or measurement system are made. If the zero or calibration drift is more than plus or minus 3% of the span value, discard the result and repeat the analysis.5.3 Quality control. A minimum of 1 sample in each batch shall be distilled and analyzed in duplicate as a precision control. If the results of the 2 analyzed differ by more than plus or minus 10% of the mean, then the system shall be reevaluated and the entire batch shall be redistilled and analyzed. 6. Calculations. 6.1 Bag sample volume, bv. **** See Formula in Attached File labeled "Figures" ****
Where
Bv = Bag sample volume in standard liters.
Mv = Indicated dry gas meter volume, in liters.
Tstd = 2930K.
Tm = Meter gas temperature, in 0K.
Pm = Meter gas pressure, in mm Hg absolute.
Pstd = 760 mm Hg.
6.2 Bag sample voc concentration, as voc, Cvoc. Cvoc = Ml/Bv
Where
Cvoc = Bag sample voc concentration, as voc, mg/std. liters.
Ml = Weight of voc liquid injected, mg.
6.3 Bag sample voc concentration, as propane, Cc3. Cc3 = Rc3*K
Where:
Cc3 = Bag sample voc concentration, as propane, mg C3/std. liter.
Rc3 = FIA reading for bag gas sample, ppm propane.
K = Conversion factor, 0.00183 mg propane/std. liter.
ppm propane
6.4 Response factor, RF. RF = Cvoc/Cc3
Where:
RF = Response factor, weight voc/weight propane.
6.5 Total voc content of the input voc containing liquid, as propane, L. **** See Formula in Attached File labeled "Figures" ****
Where:
L = Total voc content of liquid input, calculate as propane, kg.
VIJ = Initial voc weight fraction of voc liquid J.
VFJ = Final voc weight fraction of voc liquid J.
VAJ = Voc weight fraction of voc liquid J added during the test.
WIJ = Weight of voc containing liquid J at beginning of test, kg.
WFG = Weight of voc containing liquid J at end of test, kg.
WAJ = Weight of voc containing liquid J added during the test, kg.
RFJ = Response factor for voc in liquid J, weight voc/weight propane.
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Mich. Admin. Code R. 336.2007