of this method, or shall void the

sampling run. Immediately after component changes, leak-checks are optional; if such leak-checks are done, the procedure outlined in Section 4.1.4.1 above shall be used. 4.1.4.3 Post-test Leak-Check. A leakcheck is mandatory at the conclusion of each sampling run. The leak-check shall be done in accordance with the procedures outlined in Section 4.1.4.1, except that it shall be conducted at a vacuum equal to or greater than the maximum value reached during the sampling run. If the leakage rate is found to be no greater than 0.00057 m 3/min (0.02 cfm) or 4 percent of the average sampling rate (whichever is less). the results are acceptable. and no correction need be applied to the total volume of dry gas metered. If. however, a higher leakage rate is obtained, the tester shall either record the leakage rate and correct the sample volume as shown in Section 6.3 of this method, or shall void the sampling run. 4.1.5 Particulate Train Operation. During the sampling run, maintain an Isokinetic sampling rate (within 10 percent of true isokinetic unless otherwise specified by the Administrator) and a temperature around the filter of 120±14 °C (248±25 °F), or such other temperature as specified by an applicable subpart of the standards or approved by the Administrator. For each run. record the data required on a data sheet such as the one shown in Figure 5-2. Be sure to record the initial dry gas meter reading. Record the dry gas meter readings at the beginning and end of each sampling time increment, when changes in flow rates are made, before and after each leak-check, and when sampling is halted. Take other readings required by Figure 5-2 at least once at each sample point during each time increment and additional readings when significant changes (20 percent variation in velocity head readings) necessitate additional adjustments in flow rate. Level and zero the manometer. Because the manometer level and zero may drift due to vibrations and temperature changes, make periodic checks during the traverse. Clean the portholes prior to the test run to minimize the chance of sampling deposited material. To begin sampling, remove the nozzle cap, verify that the filter and probe heating systems are up to temperature, and that the pitot tube and probe are properly positioned. Position the nozzle at the first traverse point with the tip pointing directly Into the gas stream. Immediately start the pump and adjust the flow to isokinetic conditions. Nomographs are available, which aid in the rapid adjustment of the Isokinetic sampling rate without excessive computations. These nomographs are designed for use when the Type S pitot tube coefficient is 0.85±0.02, and the stack gas equivalent density (dry molecular weight) is equal to 29±4. APTD-0576 details the procedure for using the nomographs. If Cₚ and Md are outside the above stated ranges do not use the nomographs unless appropriate steps (see Citation 7 in Bibliography) are taken to compensate for the deviations. FIGURE 5-2-PARTICULATE FIELD DATA Environmental Protection Agency, EPA Plant Location Operator Date Run No Sample box No Meter box No Mater A H@ C factor Pitot tube coefficient, Cp Ambient temperature Barometric pressure Assumed moisture, % Probe length, m. (ft.) Nozzle identification No. Average calibrated nozzle diameter, CM (in.) Probe heater setting Leak rate, m3/min, (cfm) Probe liner material Static pressure, mm. Hg (in. Hg) Filter No. SCHEMATIC OF STACK CROSS SECTION 173 Gas sample temperature at Temperature of Traverse point Sampling number time Vacuum Stack term- Pressure differenperature Velocity head tial across orifice Gas sample dry gas meter Filter holder gas leaving conmeter volume temperature denser or last im- Inlet Outlet pinger (e). min. mm Hg (in. (Ts). °C (°F) (A Ps). mm mm H2O (in. H20) m³ (ft3) °C (°F) °C (°F) °C (F) °C (°F) Hg) (in.) H2O Total Average Pt. 60, App. A, Meth. 5 Pt. 60, App. A, Meth. 5 When the stack is under significant negative pressure (height of impinger stem), take care to close the coarse adjust valve before inserting the probe into the stack to prevent water from backing Into the filter holder. If necessary, the pump may be turned on with the coarse adjust valve closed. When the probe is In position. block off the openings around the probe and porthole to prevent unrepresentative dilution of the gas stream. Traverse the stack cross-section, as required by Method 1 or as specified by the Administrator. being careful not to bump the probe nozzle into the stack walls when sampling near the walls or when removing or Inserting the probe through the portholes; this minimizes the chance of extracting deposited material. During the test run, make periodic adjustments to keep the temperature around the filter holder at the proper level; add more ice and, If necessary, salt to maintain a temperature of less than 20 °C (68 °F) at the condenser/silica gel outlet. Also, periodically check the level and zero of the manometer. If the pressure drop across the filter becomes too high, making isokinetic sampling difficult to maintain, the filter may be replaced in the midst of a sample run. It is recommended that another complete filter assembly be used rather than attempting to change the filter itself. Before a new filter assembly is installed, conduct a leak-check (see Section 4.1.4.2). The total particulate weight shall Include the summation of all filter assembly catches. A single train shall be used for the entire sample run, except in cases where simultaneous sampling is required in two or more separate ducts or at two or more different locations within the same duct, or, in cases where equipment failure necessitates a change of trains. In all other situations, the use of two or more trains will be subject to the approval of the Administrator. Note that when two or more trains are used, separate analyses of the front-half and (if applicable) impinger catches from each train shall be performed, unless identical nozzle sizes were used on all trains, in which case, the front-half catches from the individual trains may be combined (as may the impinger catches) and one analysis of fronthalf catch and one analysis of Impinger catch may be performed. Consult with the Administrator for details concerning the calculation of results when two or more trains are used. At the end of the sample run, turn off the coarse adjust valve, remove the probe and nozzle from the stack, turn off the pump. record the final dry gas meter reading, and conduct a post-test leak-check, as outlined in Section 4.1.4.3. Also, leak-check the pitot lines as described in Method 2, Section 3.1; the lines must pass this leak-check, in order to validate the velocity head data. 4.1.6 Calculation of Percent Isokinetic. Calculate percent Isokinetic (see Calculations, Section 6) to determine whether the run was valid or another test run should be made. If there was difficulty in maintaining Isokinetic rates due to source conditions. consult with the Administrator for possible variance on the isokinetic rates. 4.2 Sample Recovery. Proper cleanup procedure begins as soon as the probe is removed from the stack at the end of the sampling period. Allow the probe to cool. When the probe can be safely handled. wipe off all external particulate matter near the tip of the probe nozzle and place a cap over it to prevent losing or gaining particulate matter. Do not cap off the probe tip tightly while the sampling train is cooling down as this would create a vacuum in the filter holder, thus drawing water from the impingers into the filter holder. Before moving the sample train to the cleanup site, remove the probe from the sample train, wipe off the silicone grease, and cap the open outlet of the probe. Be careful not to lose any condensate that might be present. Wipe off the silicone grease from the filter Inlet where the probe was fastened and cap it. Remove the umbilical cord from the last Impinger and cap the impinger. If a flexible line is used between the first impinger or condenser and the filter holder, disconnect the line at the filter holder and let any condensed water or liquid drain into the impingers or condenser. After wiping off the silicone grease. cap off the filter holder outlet and impinger inlet. Either ground-glass stoppers, plastic caps, or serum caps may be used to close these openings. Transfer the probe and filter-impinger assembly to the cleanup area. This area should be clean and protected from the wind so that the chances of contaminating or losing the sample will be minimized. Save a portion of the acetone used for cleanup as a blank. Take 200 ml of this acetone directly from the wash bottle being used and place It in a glass sample container labeled "acetone blank." Inspect the train prior to and during disassembly and note any abnormal conditions. Treat the samples as follows: Container No. 1. Carefully remove the filter from the filter holder and place It in Its identified petri dish container. Use a pair of tweezers and/or clean disposable surgical gloves to handle the filter. If it is necessary to fold the filter, do so such that the particulate cake is inside the fold. Carefully transfer to the petri dish any particulate matter and/or filter fibers which adhere to the filter holder gasket. by using a dry Nylon bristle brush and/or a sharp-edged blade. Seal the container. Environmental Protection Agency, EPA Container No. 2. Taking care to see that dust on the outside of the probe or other exterior surfaces does not get into the sample, quantitatively recover particulate matter or any condensate from the probe nozzle, probe fitting, probe liner, and front half of the filter holder by washing these components with acetone and placing the wash in a glass container. Distilled water may be used instead of acetone when approved by the Administrator and shall be used when specified by the Administrator: in these cases, save a water blank and follow the Administrator's directions on analysis. Perform the acetone rinses as follows: Carefully remove the probe nozzle and clean the inside surface by rinsing with acetone from a wash bottle and brushing with a Nylon bristle brush. Brush until the acetone rinse shows no visible particles, after which make a final rinse of the inside surface with acetone. Brush and rinse the inside parts of the Swagelok fitting with acetone in a similar way until no visible particles remain. Rinse the probe liner with acetone by tilting and rotating the probe while squirting acetone Into its upper end so that all inside surfaces will be wetted with acetone. Let the acetone drain from the lower end into the sample container. A funnel (glass or polyethylene) may be used to aid on transferring liquid washes to the container. Follow the acetone rinse with a probe brush. Hold the probe in an inclined position, squirt acetone Into the upper end as the probe brush is being pushed with a twisting action through the probe; hold a sample container underneath the lower end of the probe, and catch any acetone and particulate matter which is brushed from the probe. Run the brush through the probe three times or more until no visible particulate matter is carried out with the acetone or until none remains in the probe liner on visual inspection. With stainless steel or other metal probes, run the brush through in the above prescribed manner at least six times since metal probes have small crevices in which particulate matter can be entrapped. Rinse the brush with acetone, and quantitatively collect these washings in the sample container. After the brushing, make a final acetone rinse of the probe as described above. It is recommended that two people clean the probe to minimize sample losses. Between sampling runs, keep brushes clean and protected from contaminations. After ensuring that all joints have been wiped clean of silicone grease, clean the inside of the front half of the filter holder by rubbing the surfaces with a Nylon bristle brush and rinsing with acetone. Rinse each surface three times or more if needed to remove visible particulate. Make a final rinse of the brush and filter holder. Carefully rinse out the glass cyclone, also (if applicable). After all acetone washings and particulate matter have been collected in the sample container, tighten the lid on the sample container so that acetone will not leak out when it is shipped to the laboratory. Mark the height of the fluid level to determine whether or not leakage occured during transport. Label the container to clearly identify its contents. Container No. 3. Note the color of the indicating silica gel to determine if it has been completely spent and make a notation of its condition. Transfer the silica gel from the fourth Impinger to its original container and seal. A funnel may make it easier to pour the silica gel without spilling. A rubber policeman may be used as an aid in removing the silica gel from the impinger. It is not necessary to remove the small amount of dust particles that may adhere to the impinger wall and are difficult to remove. Since the gain in weight is to be used for moisture calculations, do not use any water or other liquids to transfer the silica gel. If a balance is available in the field, follow the procedure for container No. 3 in Section 4.3. Impinger Water. Treat the impingers as follows; Make a notation of any color or film in the liquid catch. Measure the liquid which is in the first three Impingers to within +1 ml by using a graduated cylinder or by weighing It to within +0.5 g by using a balance (if one is available). Record the volume or weight of liquid present. This information is required to calculate the moisture content of the effluent gas. Discard the liquid after measuring and recording the volume or weight, unless analysis of the impinger catch is required (see Note, Section 2.1.7). If a different type of condenser is used, measure the amount of moisture condensed either volumetrically or gravimetrically. Whenever possible. containers should be shipped in such a way that they remain upright at all times. 4.3 Analysis. Record the data required on a sheet such as the one shown in Figure 5-3. Handle each sample container as follows: FIGURE 5-3-ANALYTICAL DATA Plant Date Run No. Filter No. Amount liquid lost during transport Acetone blank volume, ml Acetone wash volume, ml Acetone blank concentration, mg/mg (Equation 5-4) Container Weight of particulate collected, mg number Final weight Tare weight Weight gain 1. Acetone wash blank, mg (Equation 5-5) Pt. 60, App. A, Meth. 5 Container Weight of particulate collected. mg number Final weight Tare weight Weight gain 2. Total. Less acetone blank. Weight of particulate matter. Volume of liquid water collected Impinger vol- Silica gel ume, ml weight, 9 Final. Initial. Liquid collected. Total volume collected 9* ml *Convert weight of water to volume by dividing total weight increase by density of water (1 g/ml). EC16NO91.124 Container No. 1. Leave the contents in the shipping container or transfer the filter and any loose particulate from the sample container to a tared glass weighing dish. Desiccate for 24 hours in a desiccator containing anhydrous calcium sulfate. Weigh to a constant weight and report the results to the nearest 0.1 mg. For purposes of this Section, 4.3, the term "constant weight" means a difference of no more than 0.5 mg or 1 percent of total weight less tare weight, whichever is greater, between two consecutive weighings, with no less than 6 hours of desiccation time between weighings. Alternatively. the sample may be oven dried at 105 °C (220 °F) for 2 to 3 hours, cooled in the desiccator, and weighed to a constant weight, unless otherwise specified by the Administrator. The tester may also opt to oven dry the sample at 105 °C (220 °F) for 2 to 3 hours, weigh the sample, and use this weight as a final weight. 40 CFR Ch. I (7-1-99 Edition) Container No. 2. Note the level of liquid in the container and confirm on the analysis sheet whether or not leakage occurred during transport. If a noticeable amount of leakage has occurred, either void the sample or use methods, subject to the approval of the Administrator, to correct the final results. Measure the liquid In this container elther volumetrically to +1 ml or gravimetrically to ±0.5 g. Transfer the contents to a tared 250-ml beaker and evaporate to dryness at ambient temperature and pressure. Desiccate for 24 hours and weigh to a constant weight. Report the results to the nearest 0.1 mg. Container No. 3. Weigh the spent silica gel (or silica gel plus impinger) to the nearest 0.5 g using a balance. This step may be conducted in the field. "Acetone Blank" Container. Measure acetone in this container either volumetrically or gravimetrically. Transfer the acetone to a tared 250-ml beaker and evaporate to dryness at ambient temperature and pressure. Desiccate for 24 hours and weigh to a constant weight. Report the results to the nearest 0.1 mg. NOTE: At the option of the tester, the contents of Container No. 2 as well as the acetone blank container may be evaporated at temperatures higher than ambient. If evaporation is done at an elevated temperature, the temperature must be below the boiling point of the solvent; also, to prevent "bumping." the evaporation process must be closely supervised, and the contents of the beaker must be swirled occasionally to maintain an even temperature. Use extreme care. as acetone is highly flammable and has a low flash point. 4.4 Quality Control Procedures. The following quality control procedures are suggested to check the volume metering system calibration values at the field test site prior to sample collection. These procedures are optional for the tester. 4.4.1 Meter Orifice Check. Using the callbration data obtained during the calibration procedure described in Section 5.3, determine the A H@ for the metering system orifice. The 4 H@ Is the orifice pressure differential in units of In. H2O that correlates to 0.75 cfm of air at 528° R and 29.92 in. Hg. The A H@ is calculated as follows: EC16NO91.125 Where: AH=Average pressure differential across the orifice meter, in. H 20. Tₘ=Absolute average dry gas meter temperature, R. Pta.=Barometric pressure. in. Hg. e=Total sampling time, min. Y=Dry gas meter calibration factor. dimensionless. Vₘ=Volume of gas sample as measured by dry gas meter, dcf. 0.0319=(0.0567 in. Hg/ R) x (0.75 cfm)2. Before beginning the field test (a set of three runs usually constitutes a field test). operate the metering system (i.e., pump, volume meter, and orifice) at the A H@ pressure differential for 10 minutes. Record the volume collected, the dry gas meter temperature, and the barometric pressure. Calculate a dry gas meter calibration check value, Y., as follows: Environmental Protection Agency, EPA Pt. 60, App. A, Meth. 5 EN30AU93.032 Eq. 5-10 Where: Ye=Dry gas meter calibration check value, dimensionless. 10=10 minutes of run time. Compare the Y. value with the dry gas meter calibration factor Y to determine that: 0.97Y< Ye<1.03Y If the Y. value is not within this range, the volume metering system should be investigated before beginning the test. 4.4.2 Calibrated Critical Orifice. A callbrated critical orifice, calibrated against a wet test meter or spirometer and designed to be inserted at the inlet of the sampling meter box may be used as a quality control check by following the procedure of Section 7.2. 5. Callbration Maintain a laboratory log of all calibrations. 5.1 Probe Nozzle. Probe nozzles shall be calibrated before their initial use in the field. Using a micrometer, measure the Inside diameter of the nozzle to the nearest 0.025 mm (0.001 in.). Make three separate measurements using different diameters each time, and obtain the average of the measurements. The difference between the high and low numbers shall not exceed 0.1 mm (0.004 in.). When nozzles become nicked, dented, or corroded, they shall be reshaped. sharpened, and recalibrated before use. Each nozzle shall be permanently and uniquely identified. 5.2 Pitot Tube. The Type S pitot tube assembly shall be calibrated according to the procedure outlined in Section 4 of Method 2. 5.3 Metering System. 5.3.1 Calibration Prior to Use. Before its initial use in the field, the metering system shall be calibrated as follows: Connect the metering system inlet to the outlet of a wet test meter that is accurate to within 1 percent. Refer to Figure 5.5. The wet test meter should have a capacity of 30 liters/rev (1 ft 3/ rev). A spirometer of 400 liters (14 ft3) or more capacity. or equivalent, may be used for this calibration, although a wet test meter is usually more practical. The wet test meter should be periodically calibrated with a spirometer or a liquid displacement meter to ensure the accuracy of the wet test meter. Spirometers or wet test meters of other sizes may be used, provided that the specified accuracles of the procedure are maintained. Run the metering system pump for about 15 minutes with the orifice manometer indicating a median reading as expected in field use to allow the pump to warm up and to permit the interior surface of the wet test meter to be thoroughly wetted. Then, at each of a minimum of three orifice manometer settings. pass an exact quantity of gas through the wet test meter and note the gas volume indicated by the dry gas meter. Also note the barometric pressure, and the temperatures of the wet test meter, the inlet of the dry gas meter, and the outlet of the dry gas meter. Select the highest and lowest orlfice settings to bracket the expected field operating range of the orifice. Use a minimum volume of 0.15 m³ (5 cf) at all orifice settings. Record all the data on a form similar to Figure 5.6, and calculate Y, the dry gas meter calibration factor, and AH@. the orifice calibration factor, at each orifice setting as shown on Figure 5.6. Allowable tolerances for Individual Y and AH@. values are given in Figure 5.6. Use the average of the Y values in the calculations in Section 6. EC01JN92.102 EC01JN92.103 Before calibrating the metering system. it is suggested that a leak-check be conducted. For metering systems having diaphragm pumps, the normal leak-check procedure will not detect leakages within the pump. For these cases the following leak-check procedure is suggested: make a 10-minute calibration run at 0.00057m 3/min (0.02 cfm): at the end of the run, take the difference of the measured wet test meter and dry gas meter volumes: divide the difference by 10, to get the leak rate. The leak rate should not exceed 0.00057 /min (0.02 cfm). 5.3.2 Calibration After Use. After each field use, the calibration of the metering system shall be checked by performing three calibration runs at a single, intermediate orifice setting (based on the previous field test), with the vacuum set at the maximum value reached during the test series. To adjust the vacuum, insert a valve between the wet test meter and the Inlet of the metering system. Calculate the average value of the dry gas meter calibration factor. If the value has changed by more than 5 percent, recalibrate the meter over the full range of orifice settings, as previously detailed. Alternative procedures. e.g., rechecking the orifice meter coefficient may be used, subject to the approval of the Administrator. 5.3.3 Acceptable Variation in Calibration. If the dry gas meter coefficient values obtained before and after a test series differ by more than 5 percent, the test series shall elther be voided, or calculations for the test series shall be performed using whichever meter coefficient value (i.e., before or after) gives the lower value of total sample volume. 5.4 Probe Heater Calibration. The probe heating system shall be calibrated before its initial use in the field. Use a heat source to generate air heated to selected temperatures that approximate those expected to occur in the sources to be sampled. Pass this air through the probe at a typical simple flow rate while measuring the probe inlet and outlet temperatures at various probe heater settings. For each air temperature generated, construct a graph of probe heating system setting versus probe outlet temperature. The procedure outlined in APTD-0576 can also be used. Probes constructed according to APTD-0581 need not be calibrated if the calibration curves in APTD- 0576 are used. Also, probes with outlet temperature monitoring capabilities do not require calibration. 5.5 Temperature Gauges. Use the procedure in Section 4.3 of Method 2 to calibrate In-stack temperature gauges. Dial thermometers, such as are used for the dry gas meter and condenser outlet, shall be calibrated against mercury-in-glass thermometers. 5.6 Leak Check of Metering System Shown in Figure 5-1. That portion of the sampling train from the pump to the orifice meter should be leak checked prior to initial use and after each shipment. Leakage after the pump will result in less volume being recorded than is actually sampled. The following procedure is suggested (see Figure 5- 4): Close the main valve on the meter box. Insert a one-hole rubber stopper with rubber tubing attached into the orifice exhaust pipe. Disconnect and vent the low side of the orifice manometer. Close off the low side orifice tap. Pressurize the system to 13 to 18 cm (5 to 7 in.) water column by blowing into the rubber tubing. Pinch off the tubing and observe the manometer for one minute. A loss of pressure on the manometer indicates a leak in the meter box; leaks. if present. must be corrected. 5.7 Barometer. Calibrate against a mercury barometer. 6. Calculations Carry out calculations, retaining at least one extra decimal figure beyond that of the acquired data. Round off figures after the final calculation. Other forms of the equations may be used as long as they give equivalent results. EC01JN92.104 6.1 Nomenclature An=Cross-sectional area of nozzle. m²(ft2 ). Bws=Water vapor in the gas stream. proportion by volume. Ca=Acetone blank residue concentration, mg/ mg. 40 CFR Ch. I (7-1-99 Edition) Pt. 60, App. A, Meth. 5 c₂=Concentration of particulate matter in stack gas, dry basis, corrected to standard conditions, g/dscm (g/dscf). /=Percent of isokinetic sampling. La=Maximum acceptable leakage rate for either a pretest leak check or for a leak check following a component change; equal to 0.00057 m 3/min (0.02 cfm) or 4 percent of the average sampling rate, whichever is less. L,Individual leakage rate observed during the leak check conducted prior to the "th" component change (/=1, 2, n), m3/min (cfm). Lₙ=Leakage rate observed during the posttest leak check. m³/min (cfm). ma=Mass of residue of acetone after evaporation, mg. mₙ=Total amount of particulate matter collected, mg. Mw=Molecular weight of water. 18.0 g/g-mole (18.01b/lb-mole). Phar=Barometric pressure at the sampling site. mm Hg (in. Hg). P,=Absolute stack gas pressure. mm Hg (in. Hg). Pstd=Standard absolute pressure. 760 mm Hg (29.92 in. Hg). R=Ideal gas constant. 0.06236 mm Hg-m 3/K-g- mole (21.85 in. Hg-ft 3/R-lb-mole). Tₘ=Absolute average dry gas meter temperature (see Figure 5-2). °K (°R). T.=Absolute average stack gas temperature (see Figure 5-2), °K (°R). Tatd=Standard absolute temperature, 293°K (528° R). Va=Volume of acetone blank, ml. Vaw=Volume of acetone used in wash, ml. Vₖ=Total volume of liquid collected in impingers and silica gel (see Figure 5-3). ml. Vₘ=Volume of gas sample as measured by dry gas meter. dem (dsef). Vm(sta)=Volume of gas sample measured by the dry gas meter, corrected to standard conditions, dscm (dscf). Vw(sta)=Volume of water vapor in the gas sample, corrected to standard conditions. scm (scf). v-Stack gas velocity. calculated by Method 2. Equation 2-9, using data obtained from Method 5. m/sec (ft/sec). Wo=Weight of residue in acetone wash, mg. Y=Dry gas meter calibration factor. AH-Average pressure differential across the orifice meter (see Figure 5-2). mm H₂O (in. H₂O). Density of acetone, mg/ml (see label on bottle). *wDensity of water, 0.9982 g/ml (0.002201 lb/ ml). ε=Total sampling time, min. ε,-Sampling time interval, from the beginning of a run until the first component change. min. ε=Sampling time interval. between two successive component changes, beginning with the interval between the first and second changes, min. &=Sampling time interval, from the final (nth) component change until the end of the sampling run, min. 13.6=Specific gravity of mercury. 60=Sec/min. 100=Conversion to percent. 6.2 Average Dry Gas Meter Temperature and Average Orifice Pressure Drop. See data sheet (Figure 5-2). 6.3 Dry Gas Volume. Correct the sample volume measured by the dry gas meter to standard conditions (20 °C, 760 mm Hg or 68 °F. 29.92 in. Hg) by using Equation 5-1. EC01JN92.105 Where: K1=0.3858 °K/mm Hg for metric units =17.64 °R/in. Hg for English units NOTE: Equation 5-1 can be used as written unless the leakage rate observed during any of the mandatory leak checks (i.e., the posttest leak check or leak checks conducted prior to component changes) exceeds La. If Lp or , exceeds La Equation 5-1 must be modified as follows: (a) Case I. No component changes made during sampling run. In this case, replace Vₘ in Equation 5-1 with the expression: (b) Case II. One or more component changes made during the sampling run. In this case, replace Vₘ in Equation 5-1 by the expression: EC01JN92.106 and substitute only for those leakage rates (L, or Lp) which exceed L₂ 6.4 Volume of Water Vapor. EC01JN92.107 Where: K₂=0.001333 m 3/ml for metric units =0.04707 ft3/ml for English units. 6.5 Moisture Content. Environmental Protection Agency, EPA EC16NO91.126 NOTE: In saturated or water droplet-laden gas streams, two calculations of the moisture content of the stack gas shall be made, one from the Impinger analysis (Equation 5- 3). and a second from the assumption of saturated conditions. The lower of the two values of Bws shall be considered correct. The procedure for determining the moisture content based upon assumption of saturated conditions is given in the Note of Section 1.2 of Method 4. For the purposes of this method, the average stack gas temperature from Figure 5-2 may be used to make this determination. provided that the accuracy of the Instack temperature sensor is + 1 °C (2 °F). 6.6 Acetone Blank Concentration. EC16NO91.127 6.7 Acetone Wash Blank. EC16NO91.128 6.8 Total Particulate Weight. Determine the total particulate catch from the sum of the weights obtained from Containers 1 and 2 less the acetone blank (see Figure 5-3). NOTE: Refer to Section 4.1.5 to assist in calculation of results Involving two or more fllter assemblies or two or more sampling trains. 6.9 Particulate Concentration. c₁=(0.001 gimg) (m/Vm(sxi) 6.10 Conversion Factors: Eq. 5-6 From To Multiply by scf m³ 0.02832. 9 mg 0.001 g/ft³ gr/ft³ 15.43. g/ft3 lb/ft3 2.205x10-3 g/ft³ g/m³