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Petroleum Distillate Fractions

(This method was fully evaluated with Stoddard solvent. It can also be used to determine V.M.&P. naphtha and mineral spirits.)

OSHA Method ORG-48 | November 1984

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Method Number: 48
Matrix: Air
Target concentration: 2900 mg/m3 Stoddard solvent (OSHA PEL)
Procedure: Samples are collected by drawing a known volume of air through charcoal tubes. Samples are desorbed with carbon disulfide (CS2) and analyzed by gas chromatography (GC) using a flame ionization detector (FID).
Recommended air volume
and sampling rate:

3 L at 0.2 L/min
Reliable quantitation limit: 0.77 mg/sample (260 mg/m3)
Precision: (1.96 SD)
(Section 4.3.2.)
17.8%
Status of method: Evaluated method. This method has been subjected to the established evaluation procedures of the Organic Methods Evaluation Branch.
Date: November 1984

Chemist: Michael L. Shulsky

Organic Methods Evaluation Branch
OSHA Analytical Laboratory
Salt Lake City, Utah

  1. General Discussion
    1. Background
      1. History

        Three refined petroleum mixtures are routinely analyzed at this laboratory. They are Stoddard solvent (boiling range 160-210°C), mineral spirits (boiling range 150-200°C), and petroleum distillates (V.M.&P. naphtha; boiling range 95-160°C). These mixtures will collectively be termed petroleum distillate fractions (PDF) throughout this method. All of these PDFs contain aliphatic and to a lesser extent aromatic hydrocarbons. (Ref. 5.1.)

        The procedures for collection (charcoal tubes) and analysis (GC/FID) of PDFs described in this evaluation are basically those used in NIOSH methods S380 and S382. (Ref. 5.2.) For preparation of analytical standards, these NIOSH methods require a sample of the bulk material presumed to be the source of the air contamination (this bulk material will be referred to as the "source PDF" throughout this method). The shipment of source PDFs, which are often flammable, is inconvenient and the materials sometime require distillation before use in standards. For these reasons and because similar responses to different hydrocarbons are observed using a FID (Ref. 5.3.), the use of analytical standards prepared from a PDF which is not the source PDF was investigated. In order to determine analytical conditions, it was assumed that this substitute PDF ("non-source PDF") should be of the same type, i.e. Stoddard solvent, mineral spirits, or petroleum distillates, as that used at the sampling site.

        Internal standards (Istd) are routinely used in solvent analyses at this laboratory. Since the actual constituents of PDFs are unknown, the presence of an internal standard may cause an interference with the PDF or unduly lengthen the analysis time. For these reasons, the possibility of using an external standard (Estd) procedure was examined.

        Also, in preliminary work it became apparent that the manner in which the baseline was set was a concern. If the data system was allowed to automatically set the baseline, inconsistencies in the positions to which the baseline was drawn were noticed (Figures 4.8.1. and 4.8.2.). This produced calibration errors at lower concentrations of PDFs. To overcome this problem, an evaluation of certain "integrate functions" available in the data system software which control the baseline was done (Section 4.8.4.).

        In order to evaluate the parameters of baseline, Estd, and material used to prepare analytical standards, a study was done utilizing eight different PDFs consisting of five Stoddard solvents, two V.M.&P. naphthas and one mineral spirits. These were used to spike 8 sets of 12 charcoal tubes. Each 12-tube set was quantitated using analytical standards prepared from both source and non-source PDF. There were no restrictions on the analytical conditions or GC column used for these analyses, in order to avoid having data which would apply to only certain analytical conditions. (Section 4.8.)

        The results of this study indicate several things; there is no significant difference in results obtained by using either the source or non-source PDF (Section 4.8.2.), an internal standard is not needed when consistent injection size can be maintained (Section 4.8.2.), and consistent setting of the baseline may be obtained by using "integrate functions". (Section 4.8.4.).

        Other tests performed for this evaluation were break through, storage stability, desorption efficiencies, precision of the analytical procedure, sensitivity and reliable quantitation limit. The breakthrough tests were performed with both a Stoddard solvent (Section 4.4.1.) and a V.M.&P. naphtha (Section 4.4.2.) to ensure the collection procedure would work for the more volatile constituents of a V.M.&P. naphtha. All of the other tests were performed using a Stoddard solvent but the collection and analytical procedure should also be applicable to petroleum distillates and mineral spirits.

        There are two OSHA PELs that pertain to petroleum distil late fractions. The PELs are 2900 mg/m3 for Stoddard solvent and 2000 mg/m3 for petroleum distillates (naphtha). Due to numerous synonyms and the overlapping boiling range fractions that are available, there is much confusion as to which standard is applicable in many instances. Mineral spirits, which is almost identical to Stoddard solvent in boiling range, should be compared to the Stoddard solvent PEL; while the lower boiling range petroleum distillate fractions should be compared to the petroleum distillate (naphtha) PEL.

        This evaluation shows that PDFs can be collected using charcoal with a 3-L air volume, analyzed by GC/FID and a non-source PDF may be used to prepare analytical standards.

      2. Toxic effects (This section is for information only and should not be taken as the basis of OSHA policy).

        "Short-term Exposure: Overexposure to Stoddard solvent causes irritation of the eyes, nose, and throat and may cause dizziness. Very high air concentrations may cause unconsciousness and death. Long-term Exposure: Prolonged overexposure to the liquid may cause skin irritation." (Ref. 5.4.)

        "Short-term Exposure: Overexposure to petroleum distillates may cause dizziness, drowsiness, headache, and nausea. They may also cause irritation of the eyes, throat, and skin. Long-term Exposure: Prolonged exposure may cause drying and cracking of the skin." (Ref. 5.5.)

        Men were exposed to mineral spirits concentrations of 2500 to 5000 mg/m3 for an unspecified time period. Both concentrations produced nausea and vertigo in the subjects. In another study at 4000 mg/m3 there was a prolongation of reaction time. (Ref. 5.1.)

      3. Potential workplace exposure

        NIOSH estimates that about 600,000 workers in the United States are potentially exposed to all "specialized naphthas" (Ref. 5.1.).

        Petroleum distillates (V.M.&P. naphtha) is used as a quick evaporating paint thinner. Stoddard solvent is used in the dry cleaning industry. Mineral spirits is a general purpose thinner, a dry cleaning agent, and a solvent for paint and varnish industries. (Ref. 5.1.)

      4. Physical properties (Ref. 5.1. unless otherwise stated)
        Petroleum distillates
        molecular weight: approximately 87-114
        odor: pleasant aromatic odor
        boiling range: 95 - 160°C
        specific gravity: 0.7275 - 0.7603
        color: clear, water white to yellow
        vapor pressure: 2 - 20 mm Hg at 20°C
        flashpoint: -6.7 to 12.8°C (closed cup)
        synonyms: benzine, naphtha 76, ligroin, high boiling petroleum ether
        molecular species: C7-C11

        Stoddard solvent
        molecular weight: approximately 135 - 145
        odor: kerosene-like
        boiling range: 160 - 210°C
        specific gravity: 0.75 - 0.80
        color: colorless
        vapor pressure: 4 - 4.5 mm Hg at 25°C
        flashpoint: 37.8°C (closed cup)
        synonyms: 140 flash solvent, odorless solvent and low end point solvent
        molecular species: C9-C11

        Mineral spirits
        molecular weight: approximately 144 - 169
        odor: pleasant sweet odor
        boiling range: 150 - 200°C
        specific gravity: 0.77 - 0.81
        color: clear, water white
        vapor pressure: 0.8 mm (Hg) at 20°C
        flashpoint: 30.2 - 40.5°C (closed cup)
        synonyms: white spirits, petroleum spirits, and light petrol
        molecular species: C9-C12
    2. Limit defining parameters (Air concentrations are based on the recommended air volume (3 L) and a desorption volume of 1 mL.)
      1. Detection limits

        Since PDF consist of numerous and varying components, the determination of meaningful detection limits was not considered feasible.

      2. Reliable quantitation limit

        The reliable quantitation limit is 0.77 mg/sample (260 mg/m3) This concentration was arrived at by taking all the results for calibration methods #4 and #5 from Tables 4.8.1. through 4.8.8. that were near certain concentrations, i.e. 0.3 mg/mL and 0.7 mg/mL, and finding the average recoveries, the average concentrations, and standard deviations (SD) near those concentrations. The results for samples near 0.77 mg/mL met both the requirements of 75% recovery and a precision (1.96 SD) of ±25% or better. (Section 4.2.)

      3. Sensitivity

        The sensitivity of the analytical procedure over a range representing 0.5 to 2 times the target concentration based on the recommended air volume is 300954 area units per mg/mL. This is determined by the slope of the calibration curve. (Section 4.3.3.)

      4. Recovery

        The recovery of samples used in a 15-day storage test remained above 94% (Section 4.6.). The recovery of the analyte from the collection medium during storage must be 75% or greater.

      5. Precision of the analytical procedure

        The pooled coefficient of variation obtained from replicate determinations of analytical standards at 0.5, 1, and 2 times the target concentration is 0.019 (Section 4.3.1.).

      6. Precision of the overall procedure

        The precision of the overall procedure at the 95% confidence level is ±17.8% (Section 4.3.2.). This includes an additional 5% for sampling error. The overall procedure must provide results that are ±25% or better at the 95% confidence level.

      7. Reproducibility

        Six samples spiked by liquid injection and a draft copy of this procedure were given to a chemist unassociated with this evaluation. The samples were analyzed after 2 days of storage at 22°C. The average recovery was 97.7% with a SD of ±3.53%. (Section 4.7.)

    3. Advantages
      1. The collection procedure is convenient.
      2. The analytical procedure is rapid and precise.
    4. Disadvantages

      None

  2. Sampling Procedure
    1. Apparatus
      1. A personal sampling pump which can be calibrated within ±5% of the recommended flow rate is needed.
      2. Coconut shell charcoal tubes which consist of glass tubes 7 cm long, 6-mm o.d., and 4-mm i.d., containing a 100-mg section and a 50-mg section of charcoal separated with a urethane foam plug are used. The glass tube is flame sealed at both ends. For this evaluation, SKC, Inc. charcoal tubes, lot 120, were used.
    2. Reagents

      None required

    3. Technique
      1. Immediately before sampling, break open the ends of the charcoal tube. All tubes should be from the same lot of charcoal.
      2. Connect the charcoal tube to the pump with a short piece of flexible tubing. The 50-mg portion of the charcoal tube is used as the backup section; therefore, air should flow through the 100-mg portion first.
      3. Position the tube vertically to avoid channeling through the charcoal.
      4. Air being sampled should not pass through any hose or tubing before entering the charcoal tube.
      5. Record the temperature and relative humidity of the atmosphere being sampled.
      6. Immediately after sampling, seal the ends of the tubes with the plastic caps.
      7. With each set of samples, submit at least one blank charcoal tube from the same lot as the sample tubes. The blank tube should be treated in the same manner as the samples (break ends, seal, transport) except no air is drawn through it.
      8. Transport the samples and corresponding paperwork to the laboratory for analysis.
      9. Submit source PDF whenever possible. Place the material in glass bottles with Teflon-lined caps, and transport to laboratory separately from air samples.
    4. Breakthrough

      Studies to determine the 5% breakthrough value were done near the PEL for Stoddard solvent, using a dynamically generated atmosphere with approximately 75% relative humidity at 22°C and a sampling rate of 0.203 L/min. These studies were performed using only the 100 mg portion of a charcoal tube. The average breakthrough for Stoddard solvent was 6.9 L and average capacity was 20 mg. (Section 4.4.1.). Breakthrough studies were performed with a petroleum distillate (V.M.&P.) naphtha since this type of PDF boils at a lower temperature. The average breakthrough volume for this V.M.&P. naphtha was 9.4 L and the average capacity was 20.3 mg. (Section 4.4.2.)

    5. Desorption efficiency

      Desorption efficiencies were determined at several different loadings of Stoddard solvent. These loadings corresponded to the mass of Stoddard solvent which would be collected on a charcoal tube when sampling 3 L of an atmosphere containing 0.1, 0.5, 1, and 2 times the PEL. The tubes were prepared by liquid injection of the Stoddard solvent and stored in a refrigerator for 24 h before analysis. The average desorption efficiency was 100%. (Section 4.5.)

    6. Recommended air volume and sampling rate.

      The recommended air volume is 3 L at 0.2 L/min.

    7. Interferences
      1. Since charcoal will collect vapors from many organic compounds all organics being used in significant amounts near the sampling area could decrease the capacity of the charcoal for PDF.
      2. Water vapor also may decrease the capacity of charcoal.
    8. Safety precautions
      1. Wear eye protection when breaking the ends of the charcoal tubes.
      2. Place the sampling pump on the employee in a manner so it will not interfere with the work being done.
      3. Place the charcoal tube in a holder so the broken ends are not exposed.
      4. Obey all safety regulations of the workplace.
  3. Analytical Procedure
    1. Apparatus
      1. A gas chromatograph (GC) equipped with a flame ionization detector (FID) is used for analysis. A Hewlett-Packard 5710 GC was primarily used in this evaluation.
      2. A GC column capable of separating carbon disulfide (CS2) and the internal standard, if any, from the constituents of the PDF. For this evaluation, a 20 ft by 1/8 in. stainless steel column packed with 10% SP-1000 on 80/100 Supelcoport was used.
      3. An integrator for determining peak area is needed. A Hewlett-Packard 3357 data system was used.
      4. Small vials with Teflon-lined caps for desorption of charcoal: Two-milliliter vials are preferable.
      5. Microliter syringes such as 10-µL for preparing standards and 1-µL for sample injection are needed.
      6. Pipettes for dispensing the desorbing solution may be used. A 1-mL reagent dispenser is convenient.
      7. Volumetric flasks are used for standard preparation.
      8. An analytical balance is used to prepare standards.
      9. A distillation apparatus may be needed.
    2. Reagents
      1. Carbon disulfide, reagent grade.
      2. Source PDF, when possible, from the operation where sampling was done.
      3. Internal standard compound such as hexylbenzene, reagent grade (optional).
      4. GC grade hydrogen, air and nitrogen.
      5. Desorbing solvent: CS2 or 1 µL internal standard/mL CS2.
    3. Standard preparation
      1. Analytical standards are prepared in the desorbing solvent.
      2. Source PDF received from the sampling site may be used as the analytical standard if it appears clear and colorless, and has a density in the range of 0.74-0.79 g/mL. If the bulk is colored or has a density greater than 0.79 g/mL, it needs to be distilled to separate the volatile solvents from the pigments or heavier oils before it can be used as an analytical standard.
      3. If source PDF is not submitted or is unusable, a nonsource PDF from the laboratory should be used.
      4. Standards must be prepared at four different concentrations so proper integration of the peaks may be confirmed (Section 3.5.3.). A useful range for standard concentrations is approximately 1 µL/mL to 10 µL/mL.
    4. Sample preparation
      1. The 100-mg portion of the charcoal tube is placed in a vial and the 50-mg portion is placed in a separate vial. The glass wool and urethane plugs are discarded.
      2. One milliliter of desorbing solvent is added to each vial.
      3. The vials are immediately capped and shaken periodically for 30 min before analysis.
    5. Analysis
      1. GC conditions
        oven: initial temperature 100°C for 4 min programmed to 180°C at 8°/min
        injector: 200°C
        detector: 225°C
        nitrogen (carrier): 22 mL/min
        hydrogen: 30 mL/min
        air: 250 mL/min

        injection size: 1 µL

        chromatogram: Figure 3.5.1.
      2. The data system used in this evaluation was a Hewlett-Packard 3357 which contains several "integrate functions." The integrate function termed "hold the baseline" should be used for the analyses. This function should be started before the constituents of the petroleum distillate fraction begin to elute from the column and it should be canceled after the PDF constituents have eluted or when column bleed becomes significant whichever occurs first.
      3. The areas of the peaks due to PDF constituents are added together (area summation) in the analysis of the standards and samples. The summed areas and the concentration of the analytical standards are used to determine a linear least squares fit equation. The concentration of the samples is determined by entering their summed areas into the least squares equation.
      4. If the peaks present in the samples do not elute in approximately the same time range as the standards, a comparison of the constituents in the samples and standard should be done by GC/MS to confirm that the samples do contain PDF type compounds and of what type for reporting purposes. If distinct analytes are confirmed by GC/MS, their identity and approximate concentration should be reported.
      5. Any sample above the PEL should be confirmed by GC/MS or another suitable technique.
    6. Interferences
      1. Since PDF are mixtures of aliphatic and aromatic hydrocarbons and elute from a GC in a peak cluster, it may be difficult to eliminate interfering compounds. If a large interfering peak appears in an air sample, identification by GC/MS may be necessary.
      2. It may be difficult to separate a single analyte which is requested for analysis from the PDF constituents. Changing columns such as from a polar to a non-polar (SP-1000 to an SP-2100) may help separate the analyte.
    7. Calculations
      1. PDF should be reported as mg/m3 since any ppm value would require the use of an approximate molecular weight.
      2. The air concentration in mg/m3 is determined from the mass of analyte in the sample as in the following example:

        Upon analysis, 3.5 mg was found for a sample with a 3-L air volume.

        mg/m3 = (mg/desorption efficiency)/air vol.

        mg/m3 = (3.5 mg/1.00)/(0.003 m3)

        mg/m3 = 1167 mg/m3

    8. Safety precautions
      1. Work in a hood when using solvents during sample and standard preparation.
      2. Keep solvents away from sources of high temperatures such as detectors and injectors.
      3. Avoid skin contact with solvents.
      4. Wear safety glasses at all times.
  4. Backup Data
    1. Detection limits of the analytical and overall procedure

      The determination of detection limit values is not practical in the context of a rigid definition such as a peak with a height of 5 times the baseline noise. Since PDFs may have similar constituents which have unsimilar concentrations, there is no one representative peak that can be used to determine detection limits for all PDFs.

    2. Reliable quantitation limit

      The amount of 0.77 mg/sample (260 mg/m3) is determined to be the approximate amount reliably quantitated for any applicable petroleum distillate fraction within the requirements of at least 75% recovery and a precision (1.96 SD) of ±25% or better. The injection size recommended in the analytical procedure (1 µL) was used in the determination of the reliable quantitation limit.

      Table 4.2.
      Reliable Quantitation Limit Data

      sample
      number

      calibration
      method*


      Istd

      mass (mg)
      spiked

      mass (mg)
      recovered

      %
      recovered

      1



      8



      14



      21



      31



      35



      39



      47



      51



      60



      65



      70



      76



      83

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      #4

      #5

      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no
      yes
      no

      0.789
      0.789
      0.789
      0.789
      0.789
      0.789
      0.789
      0.789
      0.777
      0.777
      0.777
      0.777
      0.777
      0.777
      0.777
      0.777
      0.753
      0.753
      0.753
      0.753
      0.753
      0.753
      0.753
      0.753
      0.754
      0.754
      0.754
      0.754
      0.754
      0.754
      0.754
      0.754
      0.779
      0.779
      0.779
      0.779
      0.779
      0.779
      0.779
      0.779
      0.761
      0.761
      0.761
      0.761
      0.761
      0.761
      0.761
      0.761
      0.776
      0.776
      0.776
      0.776
      0.776
      0.776
      0.776
      0.776

      0.873
      0.823
      0.773
      0.762
      0.847
      0.806
      0.751
      0.746
      0.812
      0.779
      0.930
      0.863
      0.753
      0.778
      0.845
      0.845
      0.643
      0.663
      0.703
      0.689
      0.684
      0.696
      0.748
      0.723
      0.658
      0.552
      0.602
      0.529
      0.655
      0.715
      0.609
      0.685
      0.828
      0.823
      0.825
      0.821
      0.820
      0.810
      0.818
      0.809
      0.793
      0.778
      0.816
      0.788
      0.824
      0.793
      0.831
      0.819
      0.900
      0.949
      0.838
      0.845
      0.851
      0.912
      0.792
      0.815

      111
      104
      98
      96
      107
      102
      95
      95
      104
      100
      120
      111
      97
      100
      109
      109
      85
      88
      93
      92
      91
      92
      99
      96
      87
      73
      80
      70
      87
      95
      81
      91
      106
      106
      106
      105
      105
      104
      105
      104
      104
      102
      107
      102
      108
      104
      109
      108
      116
      122
      108
      109
      110
      117
      102
      105

      X = 100.7%
      SD = 10.76
      1.96 SD = 21.09%

      *Explanation of calibration methods under Table 4.8.2.
    3. Precision and Sensitivity
      1. The precision of the analytical method was determined by replicate injections of analytical standards prepared at 0.5, 1, and 2 times the target concentration. The pooled coefficient of variation is 0.019.

        Table 4.3.1.
        Precision of Analytical Method

        × target conc.

        0.5×

        area counts

        1322304
        1272435
        1328744
        1350244
        1377105
        1381708

        2761497
        2731651
        2757576
        2735224
        2731653
        2693328

        5482172
        5394150
        505614
        5451850
        5466193
        5413149


        X
        SD
        CV

        1338756
            40538
             0.030

        2735155
            24375
           0.0089

        5452188
            42052
           0.0077

        CV = 0.019
      2. The precision of the overall procedure was calculated by taking the average of the SDs for methods #4 and #5 (both Istd and Estd) from Table 4.8.1. and multiplying by 1.96. This number includes ±5% for sampling error. The usual value on the cover page is the standard error of estimate from the storage test but in this evaluation this value would not have included variability for using different PDFs for analytical standards.
      3. Sensitivity is defined as the slope of the calibration curve for analytical standards from 0.5 to 2 times the target concentration. (Table 4.3.1., Figure 4.3.2.) The sensitivity is 300954 area counts/(mg/mL). The sensitivity will change depending on the detector and method of integration.
    4. Breakthrough
      1. Breakthrough was determined by sampling a dynamically generated test atmosphere of Stoddard solvent (about 2900 mg/m3 with 76% RH at 23°C), using a charcoal tube containing only the 100-mg portion of charcoal and monitoring the concentration of Stoddard solvent in the air which had passed through the charcoal. Five-percent breakthrough is defined as the point during this sampling when the air exiting the charcoal tube has a concentration of Stoddard solvent that is 5% of the test atmosphere. Two tests were performed, with 5% breakthrough air volumes of 6.5 L and 7.3 L and capacities of 19.1 mg and 21.5 mg being obtained respectively. The average 5% breakthrough air volume was 6.9 L and capacity was 20.3 mg. (Fig. 4.4.)
      2. Breakthrough tests were also performed using a petroleum distillate bulk since its boiling range is lower than Stoddard solvent and it contains more volatile constituents. The test atmospheres were about 2000 mg/m3 with 74% RH at 23°C. Three tests were performed, with 5% breakthrough air volumes of 9.6, 9.1 and 9.5 L and capacities of 20.82, 19.73 and 19.95 mg being obtained respectively. The average capacity was 20.3 mg and the average 5% breakthrough air volume was 9.4 L.
    5. Desorption efficiency

      Desorption efficiencies were determined by injecting known amounts of Stoddard solvent onto the 100-mg portion of six charcoal tubes, allowing them to sit overnight and analyzing the tubes on the next day. The average desorption efficiency over the range of 0.08 to 2 times the target concentration is 100%.

      Table 4.5.
      Desorption Efficiencies

      × target conc.
      µg/sample

      0.08×
      0.76

      0.5×
      4.55


      9.1


      18.6

      desorption
      efficiency,
      %




      X

      X = 100%

      103
      102
      99
      102
      100
      103

      102

      100
      101
      102
      102
      101
      101

      101

      100
      100
      100
      101
      101
      101

      101

      99
      99
      98
      95
      96
      94

      97

    6. Storage data

      Thirty-six samples were collected from a dynamically generated atmosphere of Stoddard solvent. The atmosphere was approximately 2900 mg/m3 and 75% RH at 22°C. Of these 36 samples, six were analyzed immediately, while the remaining 30 were stored; 15 at ambient temperature and 15 at -5°C. Approximately every third day, 3 samples from each of the storage sets were analyzed. The average recovery was 96% for ambient storage and 97% for refrigerated storage. The data of Table 4.6. are shown graphically in Figures 4.6.1. and 4.6.2.

      Table 4.6.
      Storage Tests

      storage time
      (days)

      % recovery
      (refrigerated)

      % recovery
      (ambient)

        0
        3
        7
      11
      13
      19

      99
      96
      96
      97
      96
      97

      99
      97
      97
      96
      96
      99

      99
      96
      97
      96
      96
      97

      97
      95
      95
      95
      95
      98

      99
      96
      96
      96
      96
      96

      100  
      96
      97
      97
      96
      96

    7. Reproducibility data

      Six samples, spiked by liquid injection, and a draft copy of this procedure were given to a chemist unassociated with this evaluation. The samples were analyzed after 3 days of storage at 22°C. The average recovery was 97.7% with a standard deviation of ±3.53%.

      Table 4.7.
      Reproducibility Results

      amount spiked (µg)

      amount recovered (µg)

      % recovered

      7756
      7756
      7756
      7756
      7756
      7756

      7432
      7510
      7443
      7493
      7466
      8136

      95.8
      96.8
      95.8
      96.6
      96.3
      104.9

      X = 97.7
      SD = 3.53

    8. Quantitation factors
      1. A total of 96 samples were used to evaluate differences between source and non-source PDF, automatic baseline set and controlled baseline set, and internal and external standard procedures. They were prepared by liquid injection of each of 8 PDFs on 12 charcoal tubes. These 8 sets were prepared at different times. Each set and an aliquot of the source PDF were given to the branch of this laboratory which routinely analyzes samples for PDF. The samples were desorbed with a CS2/Istd solution and analytical standards were prepared in the same solution from the source PDF and a non-source PDF chosen by the analyst. The data for these standards and samples was quantitated with nine different calibration methods. Explanations of these calibration methods are given at the bottom of Table 4.8.2. Both internal and external standard procedures were used for calibration methods #1-5. For the external standard procedure, the peak from the internal standard was ignored in all the calculations. The results from these 8 sets of PDF samples are presented in Tables 4.8.2. 4.8.9., each table represents the data from one PDF. Table 4.8.1. summarizes the data as average percent recoveries for all PDFs analyzed with each calibration method using internal and external standard procedures. For all calibration methods except #3 the summation of the peak areas for the constituents of the PDF was used to determine the response factors. Method #3 used the peak area of the largest peak in the PDF for determination of the response factors.
      2. The six analytical standards were analyzed at the same time as the samples. A linear least squares fit for each set of standards was used in all of the calibration methods except methods #3, #8 and #9. In these cases only one standard was used for calibration. Source PDF was used with calibration methods #1, #4, #6 and #8. By comparing the average results and the standard deviations obtained for method #1 to #2, #4 to #5, #6 to #7, and #8 to #9 in Table 4.8.1., it can be seen that there is no significant difference in the results; therefore, source or non-source PDF may be used to prepare analytical standards.
      3. An internal standard was present in all of the samples used but results were calculated both with the internal standard correction and without it for calibration methods #1 through #5. (Tables 4.8.1. to 4.8.9.). For all of the analyses, automatic liquid sampling devices were used with a single injection of each sample. At the bottom of Table 4.8.1. are the average results for all the PDFs using all the calibration methods calculated with both the internal standard (Istd) and external standard (Estd) procedures. From this data there appears to be no real difference between the results using the Istd correction and not (Estd). The use of an internal standard is left to the judgment of the analyst since the lengthening of the analysis and possible interferences caused by an internal standard compound will be different for each set of samples.
      4. Three different techniques of setting the baseline during analysis were investigated. One technique was to allow the data system (Hewlett-Packard 3357) to calculate the baseline and set it automatically. The other techniques require the analyst to control the baseline by using either a basic program to set the baseline and integrate the area under the chromatogram or an "integrate function" built into the data system to set the baseline.
        1. At lower concentrations of PDFs, the technique of allowing the data system to automatically set the baseline produced inconsistent results. (Figure 4.8.1. and 4.8.2.) This may be due to a parameter in the data system termed "slope sensitivity", but since single analytes are often requested in addition to PDF, setting the slope sensitivity for PDF may not be accurate for the single analytes. Calibration methods #6, #7, #8 and #9 used this technique (Tables 4.8.1. - 4.8.9.). The results in Table 4.8.1. are the average recoveries for each calibration technique with the 8 different PDFs. As can be seen in this table, the percent recoveries for each separate PDF using calibration methods #6, #7, #8 and #9 ranged from 28-143%. The average results listed at the bottom of the table for all PDFs using these four calibration methods ranged from 74-103%. Methods #6 and #7 used a linear least squares fit for calibration while methods #8 and #9 used a one point calibration. The linear least squares fit does provide results (103 and 96%) closer to the expected value but the standard deviation is larger than for methods #1-#5 in which the baseline is controlled. Therefore, controlling the baseline is recommended.
        2. Calibration methods #1 and #2 used a basic program for baseline setting and integration. This basic program was written to be used after analyzing the standards, blanks and samples. The raw data collected during an analysis is in the form of area slices which are simply detector voltages taken and stored every 0.5 s. The analyst enters into the basic program the time span over which the PDF constituents elute. The program saves the value of the first area slice in the analytical run to be used as the baseline and when the start time of the PDF is reached the program subtracts the baseline area slice from all the area slices in the specified time span and sums the differences. This summation is used as the area of PDF constituents. This program integrated the area above the baseline but not as individual peaks. The average recoveries are presented in Table 4.8.1. Since this program did not have any peak detection routine, it would not differentiate between a rise in the baseline due to a peak and column bleed. Therefore, if the baseline was not consistent and PDF constituents were eluting from the column at these times, area may be added to the PDF area which was caused by column bleed and not PDF constituents. This technique of baseline control is not recommended.
        3. The two evaluated integrate functions which control the baseline were "hold the baseline" (Figure. 4.8.2.) and "valley reset" (Figure 4.8.4.). The "valley reset" function resets the baseline every time the data system detects a zero slope or a switch from negative to positive slope of the detector output. This function is performed by the data system with start and stop times entered by the analyst. Calibration method #3 used this function and the area of the largest peak for calibration of a response factor. As can be seen in Table 4.8.1., the average results for all the PDFs analyzed with method #4 were 102(±2.3)% with the internal standard procedure and 102(±4.1)% with the external standard procedure. Comparing these results to those of the other calibration methods, method #4 is the most accurate. However, this method requires that the source PDF be used as analytical standards because the ratio of the area of the chosen peak to the others in the PDF must be constant.
        4. The "hold the baseline" function simply records the detector voltage at a certain time during the analysis and maintains that as the baseline until the function is canceled. The time to start this function is slightly before the PDF constituents begin to elute and the time to cancel it is after the constituents have eluted or when column bleed becomes significant. Both of these times are set by the analyst. After the function is canceled, the data system is free to set the baseline and it usually does correct for baseline drift due to column bleed; therefore, excess area is not added to the PDF as it was with the basic program. Calibration methods #4 and 5 used this technique. The average results and standard deviations for all PDFs for these two methods given at the bottom of Table 4.8.1. are better than the other calibration methods except #3, although this calibration method (#3) requires the use of source PDF in preparing analytical standards. Therefore, using the integrate function of "hold the baseline" is recommended and a linear least squares fit of the standards should be used to quantitate the samples.
      5. Recommendations

        For analysis of petroleum distillate fractions, either the source PDF (Section 3.3.2.) or a non-source PDF may be used to prepare analytical standards. It is recommended that the baseline be controlled with the "hold the baseline" integrate function during elution of the PDF constituents or until column bleed becomes significant whichever occurs first. Finally, either internal standard or external standard may be used with no loss in accuracy or precision.

        Table 4.8.1.
        Average Percent Recoveries
        Calculated from Tables 4.8.2. to 4.8.9.

        (see notes)

        calibration methods

        table

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        4.8.2.

        yes

        105

        96

        104

        107

        95

        97

        92

        100

        93

        no

        103

        95

        100

        102

        95

        x

        x

        x

        x


        4.8.3.

        yes

        106

        115

        104

        100

        111

        99

        101

        110

        110

        no

        108

        115

        104

        106

        109

        x

        x

        x

        x


        4.8.4.

        yes

        109

        104

        99

        91

        99

        93

        113

        91

        93

        no

        115

        106

        103

        94

        98

        x

        x

        x

        x


        4.8.5.

        yes

        103

        102

        104

        90

        83

        110

        93

        93

        91

        no

        103

        105

        102

        87

        83

        x

        x

        x

        x


        4.8.6.

        yes

        99

        97

        100

        104

        103

        95

        84

        75

        75

        no

        98

        96

        99

        103

        103

        x

        x

        x

        x


        4.8.7.

        yes

        100

        95

        104

        103

        104

        107

        110

        31

        32

        no

        99

        97

        100

        100

        102

        x

        x

        x

        x


        4.8.8.

        yes

        95

        91

        100

        106

        99

        143

        100

        29

        28

        no

        104

        93

        109

        114

        101

        x

        x

        x

        x


        4.8.9.

        yes

        119

        125

        100

        99

        100

        83

        73

        67

        73

        no

        135

        135

        95

        95

        95

        x

        x

        x

        x


        X(PDFs-Istd)

        105

        103

        102

        100

        99

        103

        96

        74

        74

        SD

        7.3

        11.5

        2.3

        6.4

        8.1

        18.0

        13.2

        30.6

        29.7


        X(PDFs-Estd)

        108

        105

        102

        100

        98

        x

        x

        x

        x

        SD

        12.1

        14.1

        4.1

        8.2

        7.7

        x

        x

        x

        x

        notes:
        1.) Explanation of Calibration methods under table 4.8.2.
        2.) Istd column: "yes" indicates internal standard was used; "no" indicates an external standard procedure used.
        3.) "x" under calibration methods #6, 7, 8 9 indicates no data was collected with an external standard procedure.

        Table 4.8.2.
        Percent Found for Stoddard solvent A

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        1

        789

        yes

        104

        96

        102

        111

        98

        96

        91

        101

        93

        no

        102

        93

        97

        104

        96

        x

        x

        x

        x

        2

        3159

        yes

        101

        94

        103

        106

        94

        99

        93

        102

        94

        no

        100

        92

        98

        100

        93

        x

        x

        x

        x

        3

        4739

        yes

        102

        94

        104

        107

        95

        99

        92

        101

        93

        no

        101

        94

        100

        103

        95

        x

        x

        x

        x

        4

        237

        yes

        120

        103

        107

        109

        97

        91

        87

        96

        88

        no

        108

        98

        102

        101

        94

        x

        x

        x

        x

        5

        6318

        yes

        103

        94

        104

        104

        93

        103

        96

        104

        96

        no

        101

        94

        101

        101

        93

        x

        x

        x

        x

        6

        3159

        yes

        102

        95

        105

        105

        94

        102

        102

        105

        9

        no

        103

        95

        101

        101

        94

        x

        x

        x

        x

        7

        6318

        yes

        103

        94

        104

        106

        94

        101

        93

        102

        94

        no

        101

        95

        101

        103

        95

        x

        x

        x

        x

        8

        789

        yes

        102

        94

        101

        107

        95

        91

        86

        95

        88

        no

        100

        92

        97

        102

        95

        x

        x

        x

        x

        9

        4739

        yes

        103

        95

        105

        107

        95

        102

        95

        104

        96

        no

        103

        95

        102

        104

        96

        x

        x

        x

        x

        10

        2369

        yes

        102

        95

        104

        108

        96

        97

        92

        101

        93

        no

        103

        95

        101

        104

        97

        x

        x

        x

        x

        11

        237

        yes

        115

        99

        105

        104

        92

        86

        81

        90

        83

        no

        105

        95

        101

        99

        91

        x

        x

        x

        x

        12

        2369

        yes

        104

        97

        106

        110

        98

        99

        94

        97

        95

        no

        106

        97

        104

        107

        99

        x

        x

        x

        x

        notes:
        1.) Calibration method #1 uses as analytical standards the source PDF, the basic program for peak integration and area summation of the standards for calibration.
        2.) Calibration method #2 uses as analytical standards a non-source PDF, otherwise the same as #1.
        3.) Calibration method #3 uses the source PDF, "valley reset" for peak integration and a single peak in the standards for calibration.
        4.) Calibration method #4 uses as analytical standards the source PDF, "hold the baseline" for peak integration and area summation of standards for calibration.
        5.) Calibration method #5 uses as analytical standards a non-source PDF, otherwise the same as #4.
        6.) Calibration method #6 uses as analytical standards the source PDF, the data system sets the baseline for peak integration, and area summation of standards for calibration.
        7.) Calibration method #7 uses as analytical standards a non-source PDF, otherwise the same as #6.
        8.) Calibration method #8 uses as analytical standards the source PDF, the data system sets the baseline for peak integration, and area summation of only one standard for calibration.
        9.) Calibration method #9 uses as analytical standards a non-source PDF, otherwise the same as #8.

        Table 4.8.3.
        Percent Found for Stoddard Solvent B

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        13

        3109

        yes

        112

        119

        111

        116

        128

        103

        95

        103

        103

        no

        107

        114

        106

        111

        118

        x

        x

        x

        x

        14

        777

        yes

        111

        120

        108

        104

        120

        125

        122

        137

        136

        no

        108

        116

        103

        100

        111

        x

        x

        x

        x

        15

        233

        yes

        122

        141

        103

        89

        96

        79

        132

        136

        136

        no

        117

        125

        94

        lost

        89

        x

        x

        x

        x

        16

        5440

        yes

        106

        113

        106

        106

        117

        107

        98

        105

        105

        no

        104

        110

        104

        104

        112

        x

        x

        x

        x

        17

        7772

        yes

        106

        114

        104

        105

        116

        107

        103

        106

        105

        no

        104

        110

        103

        105

        112

        x

        x

        x

        x

        18

        233

        yes

        107

        125

        103

        79

        78

        55

        101

        114

        113

        no

        108

        116

        103

        lost

        76

        x

        x

        x

        x

        19

        4663

        yes

        101

        108

        101

        lost

        113

        99

        89

        98

        98

        no

        107

        114

        106

        107

        115

        x

        x

        x

        x

        20

        3109

        yes

        100

        106

        100

        99

        114

        97

        86

        97

        97

        no

        109

        116

        107

        106

        119

        x

        x

        x

        x

        21

        777

        yes

        99

        108

        100

        97

        109

        105

        102

        118

        118

        no

        104

        112

        103

        100

        109

        x

        x

        x

        x

        22

        7772

        yes

        104

        112

        103

        104

        114

        105

        101

        104

        104

        no

        106

        113

        107

        108

        115

        x

        x

        x

        x

        23

        5440

        yes

        103

        110

        104

        104

        115

        104

        95

        103

        103

        no

        110

        117

        111

        111

        119

        x

        x

        x

        x

        24

        4663

        yes

        100

        107

        101

        102

        113

        99

        89

        98

        98

        no

        107

        114

        108

        108

        116

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.4.
        Percent Found for V.M.&P. Naphtha A

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        25

        7528

        yes

        103

        102

        104

        89

        98

        102

        104

        102

        104

        no

        120

        105

        106

        94

        98

        x

        x

        x

        x

        26

        5270

        yes

        102

        104

        103

        89

        97

        101

        105

        102

        104

        no

        112

        107

        107

        95

        99

        x

        x

        x

        x

        27

        7528

        yes

        106

        104

        107

        92

        100

        105

        107

        105

        107

        no

        119

        105

        106

        94

        98

        x

        x

        x

        x

        28

        1506

        yes

        106

        107

        98

        92

        100

        93

        105

        93

        95

        no

        110

        109

        105

        98

        102

        x

        x

        x

        x

        29

        3011

        yes

        100

        103

        97

        88

        96

        98

        104

        98

        100

        no

        106

        106

        104

        94

        98

        x

        x

        x

        x

        30

        226

        yes

        172

        119

        96

        100

        110

        72

        148

        65

        66

        no

        177

        121

        101

        100

        102

        x

        x

        x

        x

        31

        753

        yes

        98

        99

        94

        85

        93

        88

        111

        86

        88

        no

        99

        99

        99

        88

        92

        x

        x

        x

        x

        32

        5270

        yes

        99

        102

        101

        88

        96

        101

        103

        100

        102

        no

        106

        103

        103

        92

        96

        x

        x

        x

        x

        33

        753

        yes

        101

        103

        94

        91

        99

        91

        114

        89

        91

        no

        101

        102

        98

        92

        96

        x

        x

        x

        x

        34

        1506

        yes

        100

        106

        98

        92

        100

        93

        105

        93

        95

        no

        103

        108

        105

        97

        101

        x

        x

        x

        x

        35

        226

        yes

        124

        103

        95

        97

        106

        71

        146

        64

        65

        no

        126

        103

        99

        93

        96

        x

        x

        x

        x

        36

        3011

        yes

        97

        103

        98

        89

        97

        98

        104

        98

        100

        no

        103

        106

        105

        95

        99

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.5.
        Percent Found for V.M.&P. Naphtha B

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        37

        3768

        yes

        103

        98

        106

        96

        88

        103

        98

        101

        99

        no

        95

        93

        97

        86

        83

        x

        x

        x

        x

        38

        6029

        yes

        102

        100

        110

        96

        87

        103

        99

        103

        101

        no

        95

        98

        97

        86

        82

        x

        x

        x

        x

        39

        754

        yes

        102

        100

        101

        87

        80

        106

        84

        87

        85

        no

        94

        94

        93

        73

        70

        x

        x

        x

        x

        40

        2261

        yes

        106

        100

        105

        97

        89

        100

        92

        95

        93

        no

        99

        95

        98

        88

        85

        x

        x

        x

        x

        41

        301

        yes

        95

        109

        100

        72

        66

        111

        54

        58

        57

        no

        90

        106

        94

        52

        50

        x

        x

        x

        x

        42

        4522

        yes

        101

        97

        102

        92

        85

        100

        97

        100

        98

        no

        104

        105

        104

        94

        90

        x

        x

        x

        x

        43

        3768

        yes

        104

        99

        105

        94

        86

        104

        99

        102

        100

        no

        107

        106

        107

        96

        86

        x

        x

        x

        x

        44

        2261

        yes

        106

        99

        104

        95

        87

        102

        95

        97

        95

        no

        109

        104

        108

        98

        94

        x

        x

        x

        x

        45

        301

        yes

        113

        124

        101

        77

        70

        127

        70

        74

        73

        no

        117

        129

        105

        79

        75

        x

        x

        x

        x

        46

        6028

        yes

        102

        100

        111

        95

        87

        103

        100

        103

        101

        no

        107

        114

        110

        98

        94

        x

        x

        x

        x

        47

        754

        yes

        106

        104

        191

        87

        81

        157

        133

        89

        87

        no

        113

        111

        108

        95

        91

        x

        x

        x

        x

        48

        4522

        yes

        103

        97

        106

        94

        86

        103

        99

        102

        100

        no

        109

        111

        112

        100

        95

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.6.
        Percent Found for Stoddard Solvent D

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        49

        3897

        yes

        99

        99

        101

        100

        98

        100

        90

        88

        88

        no

        98

        97

        98

        98

        97

        x

        x

        x

        x

        50

        6235

        yes

        99

        98

        101

        98

        98

        94

        88

        88

        88

        no

        97

        96

        99

        97

        97

        x

        x

        x

        x

        51

        779

        yes

        96

        92

        97

        106

        106

        96

        78

        61

        61

        no

        95

        91

        96

        106

        105

        x

        x

        x

        x

        52

        545

        yes

        92

        87

        95

        105

        105

        105

        82

        59

        59

        no

        91

        85

        94

        104

        104

        x

        x

        x

        x

        53

        6235

        yes

        100

        99

        102

        99

        98

        95

        88

        89

        88

        no

        100

        99

        102

        99

        99

        x

        x

        x

        x

        54

        2338

        yes

        102

        101

        102

        106

        105

        109

        95

        89

        89

        no

        100

        99

        100

        104

        104

        x

        x

        x

        x

        55

        545

        yes

        99

        94

        101

        112

        112

        69

        82

        60

        60

        no

        98

        93

        100

        112

        112

        x

        x

        x

        x

        56

        3897

        yes

        101

        100

        102

        101

        100

        101

        91

        89

        89

        no

        100

        100

        101

        100

        100

        x

        x

        x

        x

        57

        1559

        yes

        100

        99

        101

        105

        105

        94

        79

        70

        70

        no

        101

        99

        101

        106

        105

        x

        x

        x

        x

        58

        2338

        yes

        101

        100

        101

        103

        102

        89

        77

        71

        71

        no

        100

        99

        100

        101

        101

        x

        x

        x

        x

        59

        1559

        yes

        100

        98

        101

        105

        104

        93

        79

        70

        70

        no

        102

        100

        102

        107

        106

        x

        x

        x

        x

        60

        779

        yes

        100

        96

        100

        105

        105

        99

        80

        63

        63

        no

        767

        739

        769

        810

        809

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.7.
        Percent Found for Stoddard Solvent D

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        61

        3045

        yes

        102

        100

        102

        103

        102

        102

        104

        34

        34

        no

        96

        100

        96

        98

        103

        x

        x

        x

        x

        62

        3045

        yes

        102

        101

        102

        104

        103

        102

        104

        34

        34

        no

        96

        101

        97

        98

        103

        x

        x

        x

        x

        63

        6853

        yes

        103

        102

        104

        102

        102

        103

        105

        34

        34

        no

        100

        101

        99

        98

        102

        x

        x

        x

        x

        64

        1523

        yes

        98

        94

        96

        101

        104

        100

        102

        30

        31

        no

        97

        98

        94

        100

        101

        x

        x

        x

        x

        65

        761

        yes

        97

        89

        99

        104

        107

        114

        116

        29

        30

        no

        100

        92

        97

        102

        104

        x

        x

        x

        x

        66

        533

        yes

        99

        87

        119

        107

        110

        125

        127

        28

        28

        no

        106

        90

        117

        105

        106

        x

        x

        x

        x

        67

        6853

        yes

        99

        97

        100

        98

        101

        98

        100

        33

        33

        no

        98

        99

        97

        96

        97

        x

        x

        x

        x

        68

        533

        yes

        99

        87

        100

        107

        108

        125

        127

        28

        29

        no

        105

        88

        96

        103

        106

        x

        x

        x

        x

        69

        1523

        yes

        98

        94

        101

        101

        103

        100

        102

        30

        31

        no

        96

        97

        97

        98

        100

        x

        x

        x

        x

        70

        761

        yes

        101

        93

        119

        108

        109

        117

        119

        30

        31

        no

        102

        94

        115

        104

        108

        x

        x

        x

        x

        71

        4568

        yes

        100

        99

        99

        100

        101

        99

        102

        33

        34

        no

        9699

        95

        96

        99

        x

        x

        x

        x

        72

        4568

        yes

        100

        98

        104

        100

        102

        99

        101

        33

        34

        no

        96

        100

        100

        97

        99

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.8.
        Percent Found for Stoddard solvent E

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        73

        7756

        yes

        104

        94

        103

        99

        92

        106

        102

        35

        34

        no

        108

        96

        111

        106

        94

        x

        x

        x

        x

        74

        2327

        yes

        103

        98

        103

        103

        95

        153

        105

        35

        34

        no

        110

        100

        112

        109

        97

        x

        x

        x

        x

        75

        3878

        yes

        104

        97

        102

        100

        93

        132

        102

        35

        34

        no

        110

        98

        111

        106

        95

        x

        x

        x

        x

        76

        776

        yes

        89

        88

        96

        116

        108

        139

        77

        17

        16

        no

        99

        88

        103

        122

        109

        x

        x

        x

        x

        77

        5429

        yes

        101

        94

        102

        97

        90

        116

        98

        34

        32

        no

        108

        96

        109

        104

        93

        x

        x

        x

        x

        78

        7756

        yes

        102

        93

        101

        96

        89

        103

        97

        33

        32

        no

        110

        97

        112

        106

        94

        x

        x

        x

        x

        79

        388

        yes

        78

        81

        99

        130

        125

        206

        112

        17

        16

        no

        91

        80

        106

        140

        126

        x

        x

        x

        x

        80

        3878

        yes

        101

        94

        103

        98

        91

        129

        99

        34

        33

        no

        108

        97

        110

        105

        94

        x

        x

        x

        x

        81

        5429

        yes

        102

        94

        103

        99

        92

        118

        100

        35

        33

        no

        111

        99

        112

        109

        97

        x

        x

        x

        x

        82

        2327

        yes

        100

        96

        102

        101

        94

        151

        109

        34

        33

        no

        110

        99

        112

        108

        97

        x

        x

        x

        x

        83

        776

        yes

        84

        83

        95

        110

        102

        170

        97

        24

        23

        no

        96

        86

        104

        117

        105

        x

        x

        x

        x

        84

        388

        yes

        77

        79

        98

        122

        114

        199

        108

        16

        15

        no

        92

        80

        107

        132

        118

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.2.

        Table 4.8.9.
        Results for Mineral Spirits A

        (see notes)

        calibration methods

        sample

        µg

        Istd

        #1

        #2

        #3

        #4

        #5

        #6

        #7

        #8

        #9

        85

        7673

        yes

        109

        113

        106

        101

        106

        103

        99

        94

        100

        no

        100

        98

        88

        91

        90

        x

        x

        x

        x

        86

        230

        yes

        186

        200

        108

        90

        88

        57

        109

        43

        46

        no

        270

        275

        98

        82

        94

        x

        x

        x

        x

        87

        1534

        yes

        149

        158

        119

        129

        135

        110

        93

        86

        92

        no

        144

        145

        107

        119

        117

        x

        x

        x

        x

        88

        5371

        yes

        107

        110

        103

        102

        107

        100

        92

        86

        92

        no

        115

        113

        106

        108

        107

        x

        x

        x

        x

        89

        7673

        yes

        106

        110

        103

        96

        101

        107

        104

        99

        106

        no

        116

        113

        107

        102

        101

        x

        x

        x

        x

        90

        537

        yes

        210

        224

        65

        123

        114

        50

        40

        37

        40

        no

        226

        228

        67

        108

        106

        x

        x

        x

        x

        91

        2302

        yes

        110

        115

        104

        104

        107

        89

        76

        70

        75

        no

        112

        112

        101

        102

        99

        x

        x

        x

        x

        92

        1534

        yes

        107

        113

        106

        106

        108

        91

        76

        70

        75

        no

        112

        112

        103

        103

        102

        x

        x

        x

        x

        93

        537

        yes

        61

        65

        71

        62

        56

        39

        32

        30

        31

        no

        73

        74

        64

        54

        54

        x

        x

        x

        x

        94

        230

        yes

        82

        89

        106

        72

        78

        45

        36

        33

        35

        no

        143

        149

        96

        67

        66

        x

        x

        x

        x

        95

        5371

        yes

        99

        103

        101

        93

        97

        110

        101

        95

        102

        no

        106

        105

        106

        99

        97

        x

        x

        x

        x

        96

        2302

        yes

        104

        110

        106

        106

        110

        90

        77

        71

        76

        no

        103

        103

        104

        104

        102

        x

        x

        x

        x

        note: Explanation of calibration methods under Table 4.8.1.

     

    Figure 3.5.1. Chromatogram of PDF standard. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 3.5.1. Chromatogram of PDF standard.

    Figure 4.3.2. Sensitivity. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.3.2. Sensitivity.

    Figure 4.4. Breakthrough curve. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.4. Breakthrough curve.

    Figure 4.5. Desorption efficiencies. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.5. Desorption efficiencies.

    Figure 4.6.1. Ambient storage. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.6.1. Ambient storage.

    Figure 4.6.2. Refrigerated storage. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.6.2. Refrigerated storage.

    Figure 4.8.1. Automatic baseline set. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.8.1. Automatic baseline set.

    Figure 4.8.2. Automatic baseline set. - For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.8.2. Automatic baseline set.

    Figure 4.8.3. Controlled baseline with 'hold the baseline' function.- For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.8.3. Controlled baseline with "hold the baseline" function.

    Figure 4.8.4. Controlled baseline with 'valley reset' function.- For problems with accessibility in using figures, illustrations and PDFs in this method, please contact the SLTC at (801) 233-4900.

    Figure 4.8.4. Controlled baseline with "valley reset" function.

  5. References
    1. "Criteria for a Recommended Standard...Occupational Exposure to Refined Petroleum Solvents"; Department of Health, Education and Welfare, National Institute for Occupational Safety and Health: Cincinnati, OH, 1977 (DHEW) (NIOSH) Publ. (U.S.) No. 77-192.
    2. "NIOSH Manual of Analytical Methods", 2nd ed.; Department of Health, Education and Welfare, National Institute for Occupational Safety and Health: Cincinnati, OH, 1977; Vol. 3, Methods S380 and S382; DHEW (NIOSH) Publ. (U.S.) No. 77-157-C.
    3. Drushel, Harry V. Journal of Chromatographic Science. 21, August 1983, p 375.
    4. "Occupational Health Guideline for Stoddard Solvent", Department of Health and Human Services, National Institute for Occupational Safety and Health: U.S. Government Printing Office, Washington, D.C., 1978; Publ. 81-123.
    5. "Occupational Health Guideline for Petroleum Distillates", Department of Health and Human Services, National Institute for Occupational Safety and Health: U.S. Government Printing Office, Washington, D.C. 1978; Publ. 81-123.
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