1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW16639 Paint Material Odor Assessment - Olfactometry Copyright 2011 General Motors Company All Rights Reserved November 2011 Originating Department: North American Engineering Standards Page 1 of 13 1 Scope This standard covers the requirements for a
2、ssessing the relative odor potential of automotive paint materials. It includes liquid paint materials that are applied by spraying, electrodeposition primers and solvents. It also includes three methods for sample collection and the appropriate use of these methods. Note: Nothing in this standard s
3、upercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. Note: All materials supplied to this standard must comply with the requirements listed in GMW3059 Restricted and Reportable Chemicals 1.1 P
4、urpose. Not applicable. 1.2 Foreword. Not applicable. 1.3 Applicability. Not applicable. 2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM 679 ASTM E544 2.2 GM Standards/Specifications. GMW3059 2.3 Additional
5、References. Air & Waste Management Association (AWMA) E6 Odor Committee Standard 3 Resources 3.1 Facilities. Not applicable. 3.2 Equipment. Equipment requirements are separated into four categories: General, Method A, Method B and Method C. 3.2.1 General Equipment. a. Triangular dynamic dilution olf
6、actometer capable of supplying regulated concentrations of sample to the test port at calibrated flow rates. b. Butanol sample bottles from 15 to 2000 ppm with a step factor of 2 for each intensity (8 point scale). c. Tedlar sampling bags with a 10 to 40 L volume capacity or as determined by olfacto
7、meter setup. d. Volumetric flow rate measurement equipment capable of measuring to 0.01 L/minute. e. Teflon Tubing. 3.2 mm ( inch) and 6.4 mm ( inch )outer diameter (OD). f. Thermometer (for ambient temperature). g. Barometer. h. Stop watch. i. Ultrasonic cleaner. j. Pure nitrogen cylinder. Copyrigh
8、t General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16639 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 2 of 13 k. Mat
9、heson Dual Stage Regulator with 0 psig to 200 psig delivery pressure range. 3.2.2 Method A Equipment. a. Dry filter spray booth. b. Cup guns or pressure pots (0.8 L to 2 L). c. Rigid container odor sampling lung and evacuation pump. d. Sampling probe with minimum 6.4 mm ( inch) inner diameter (ID).
10、e. 100 mm 300 mm phosphate plain steel panels. Note: Pretreatment as defined by responsible engineer. 3.2.3 Method B Equipment. a. Force-dry, gas-fired oven capable of 200 C (400 F). b. 100 mm 300 mm phosphate plain steel panels. Note: Use pretreatment as defined by responsible engineer. 3.2.4 Metho
11、d C Equipment. a. Oven for liquid evaporation. Varian Aerograph Series 1200 Chromatograph or equivalent. b. Digital flow meter capable of measuring 1 L to 2 L/minute with a resolution of 0.001 L/minute (Gilian Primary Standard Airflow Calibrator (Gilibrator) or equivalent). c. Teflon tubing with int
12、ernal diameter of 3.2 mm ( inch). d. Analytical balance capable of weighing 20 g within 0.0001 g. e. Syringes 10 L to 250 L with spare needles. (Hamilton Model 1801RN and Model 1825RN Gastight Syringes or equivalent). f. Ultrasonic cleaner. g. Septa for gas chromatograph (GC) injection port. 3.3 Tes
13、t Vehicle/Test Piece. Not applicable. 3.4 Test Time. Not applicable. 3.5 Test Required Information. Not applicable. 3.6 Personnel/Skills. Not applicable. 4 Procedure 4.1 Preparation. Not applicable. 4.2 Conditions. Not applicable. 4.2.1 Environmental Conditions. Not applicable. 4.2.2 Test Conditions
14、. Deviations from the requirements of this standard shall have been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 Test Procedure. Basic methodology for sample collection and odor measurement protocol is per guideline
15、s set forth in the Air Waste Management Association (AWMA) E6 Odor Committee Standard (for Method A). Exceptions and clarifications for GM testing and data reporting are contained in this procedure. All testing is to be done using a side-by-side relative comparison approach. For example, new materia
16、ls should be compared to the existing materials they intend to replace. 4.3.1.1 Sample Collection. All odor samples must be collected using odor-free, chemically inert, nonreactive, low permeability, smooth materials. Line lengths from sampling probe to the sampling bag must be kept to a minimum. 4.
17、3.1.1.1 Sample Bags. Bags must be Tedlar with a 10 L to 40 L capacity unless otherwise agreed upon prior to start of test. 4.3.1.1.2 Conditioning. Preconditioning must be done with both inert gas and sample gas. Use an agreed upon method. 4.3.1.1.3 Replication. Three (3) runs per sample must be done
18、 for each collection method. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16639 Copyright 2011 General Motors Company All Rights Reser
19、ved November 2011 Page 3 of 13 4.3.1.1.4 Documentation. Information requirements are shown in Tables A3a and A3b. 4.3.1.2 Collection Methods. There are three methods for collecting odor samples based on the type of material being evaluated. 4.3.1.2.1 Method A Paint Spray Application. This method is
20、used for simulation of relative odor potential of liquid paints that are spray-applied. Sampling for this method is done in the exhaust stack from the booth per Figure A1. Typical materials evaluated are liquid basecoats, clearcoats or primers. 4.3.1.2.1.1 Sample Preparation. Reduce paint as require
21、d to simulate production or use a production sample at spray viscosity. Determine initial paint properties volatile organic compounds (VOC), weight solids, etc.) and the amount of paint sprayed by both weight and volume. 4.3.1.2.1.2 Replication. Spray three 100 mm 300 mm panels per run. There should
22、 be three runs per sample unless otherwise agreed upon. 4.3.1.2.1.3 Sampling Time is 1 Minute. Initiate sampling simultaneously with the initiation of spraying. Sample the exhaust stack continuously during spraying. Specify draw rate in Liters per minute. 4.3.1.2.1.4 Paint Colors. Odor analysis for
23、a new topcoat technology must be done with a minimum palette of White, Medium Red Mica and Light Metallic plus clearcoat. Odor analysis for a new primer-surfacer technology must be done on a minimum of Gray and Red. Specific color Codes (i.e., WAXXXX or L), will be agreed upon at test initiation. Te
24、sting of additional colors may be required prior to plant implementation, depending on color-to-color solvent variation and plant location. 4.3.1.2.2 Method B Oven Bake. This method is typically used for electrodeposition primer, powder paint, liquid paints that may give off odorous by-products, sea
25、lers and adhesives. Materials are baked at upper bake limits and samples are collected from the oven exhaust air per Figure A2. 4.3.1.2.2.1 Sample Preparation. Apply target films of electrodeposition primer or powder. A minimum of 6 (six) panels per run must be used. 4.3.1.2.2.2 Sampling Time. Heat
26、oven to upper limit of bake schedule and insert test specimens. Bake for 30 minutes and sample continuously at constant flow rate to the bag. 4.3.1.2.3 Method C Head Space. This method should be used for determining odor threshold of solvents and for screen testing liquid paints for impact of formul
27、ation changes. See Figure A3 for equipment layout. 4.3.1.2.3.1 Sample Preparation. Paint samples must be at spray viscosity and thoroughly mixed. 4.3.1.2.3.2 Test Conditions. For paint samples, the following settings of the gas chromatograph should be used: x Program Mode: ISO x Injector Temperature
28、: 45 C (113 F) x Column Oven: Oven and fan x Oven Temperature: 45 C (113 F) x Other Settings: Not used 4.3.1.2.3.3 Sample Size. Use 50 L for paint unless otherwise agreed upon. Quantity of sample should be such that the resulting odor detection threshold (D/T) is between 50 and 500 odor units (OU).
29、Select a clean syringe in the proper size (250 L for 50 L to 500 L liquid volume, 10 L for 10 L liquid volume) and flush the syringe with the liquid sample at least three times. 4.3.1.2.3.4 General Procedure. Connect a clean, dry Teflon tube to the gas chromatograph (approximately 0.3 cm OD by 100 c
30、m long). With power on, turn nitrogen cylinder on and adjust the regulator for delivery pressure of about 100 psig. Extract the exact appropriate volume of liquid. Weigh the filled syringe and record the weight as the initial weight. 4.3.1.2.3.4.1 Measure the flow rate at the sample line outlet usin
31、g the Gilibrator. Adjust the cylinder regulator to give a steady flow rate of 0.8 L to 1.2 L/minute. Record this as the initial flow rate. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license f
32、rom IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16639 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 4 of 13 4.3.1.2.3.4.2 Connect a cleaned and labeled 30 L Tedlar bag to the outlet of the sample line. Collect some nitrogen and flush the bag. Reconnect the bag to the
33、 sample line outlet and start timing immediately. Collect the nitrogen for approximately 2 minutes and inject the liquid sample into the injection port. Allow the needle to reside in the injector port for at least 1 minute to evaporate the droplet at the tip. Re-weigh the syringe and record as the f
34、inal weight. 4.3.1.2.3.4.3 Continue running for 30 minutes with the nitrogen on. Remove the Tedlar bag at the end of the sampling period and record the sampling time. 4.3.1.2.3.4.4 Measure the flow rate immediately and record this as the final flow rate. If the difference between initial and final r
35、ate is greater than 10%, the sample must be discarded and the cause of variance must be ascertained. 4.3.1.2.3.4.5 Remove the sample line and flush it with acetone and then distilled water. Then clean it in an ultrasonic cleaner for at least 15 minutes. Reclean with distilled water and dry with clea
36、n, dry air. 4.3.1.2.3.5 Calculations. The volume of nitrogen used to fill the sample bag is calculated using the average of the initial and final flow rates multiplied by the total sampling time, correcting for temperature and pressure. The concentration of liquid in the sample bag is calculated by
37、dividing the weight of the liquid injected in milligrams by the volume of nitrogen in cubic meters. This concentration, divided by the threshold odor value gives the threshold concentration in milligram per cubic meter (mg/m3). 4.3.1.3 Odor Test Protocol. The time interval between sample collection
38、and odor panel evaluation must be no more than 24 hours. As a general practice, analysis should be conducted with 8 hours of sample collection. 4.3.1.3.1 Panel Selection. Panelists must be screened for sensitivity to n-Butanol, which is the reference standard, and trained in the use of olfactometer
39、equipment. Report an average sensitivity for each group. 4.3.1.3.2 Olfactometer. A dynamic olfactometer should be used in accordance with ASTM 679. Any deviation must be discussed with the appropriate engineer for approval prior to testing. 4.3.1.3.3 Flow Rate. The sample gas flow rate must be betwe
40、en 5 and 10 L/minute per sniff port. 4.3.1.3.4 Sample Dilution. The maximum step factor between subsequent concentrations is 2. The same dilution factor must be used for each replicate. Report any variance in step factor from concentration to concentration. 4.3.1.3.5 Odor Measurements. The following
41、 odor parameters will be determined by measurement or calculation and reported. 4.3.1.3.5.1 Dilution to Detection Threshold (D/Td). Where the Detection Threshold (Td) is the lowest concentration of an odorant at which an odorized sample can be distinguished from non-odorous air by 50% of the group o
42、f observers. Note: This may also be referred to as ED50. 4.3.1.3.5.2 Dilution to Recognition Threshold (D/Tr). Where the Recognition Threshold, Tr is the lowest concentration of an odorant at which the odor character can be described/characterized by 50% of the group of observers. 4.3.1.3.5.3 Odor U
43、nit (OU). An odor unit is the amount of odor produced by a given Dilution at Detection Threshold (D/Td) by the volume or weight of paint sprayed. Report OUv, and OUw when using collection Method A. Report by volume when using collection Methods B and C. 4.3.1.3.5.3.1 OUv = Odor units based on volume
44、 of paint sprayed in milliliters for odor sample collection in the stack. 4.3.1.3.5.3.2 OUw = Odor units based on weight in gram (g) of paint sprayed for odor sample collection in the stack. 4.3.1.3.5.4 Intensity (I). Intensity is the comparison of the odorant strength, Tr, of n-Butanol in water. Bu
45、tanol samples are prepared per ASTM E544, Method B on an 8-point scale which starts at a concentration of 15 ppm and goes to 2000 ppm. See Table A1 for the relationship between the rating scale and the concentration level of n-Butanol in water. 4.3.1.3.5.5 Odor Character Description. This is a gener
46、al description of odor using Harpers Scale of odor-quality descriptors as a guide. See Table A2. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STAND
47、ARDS GMW16639 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 5 of 13 4.3.1.4 Other Definitions and Calculations. 4.3.1.4.1 Dilution Air. The odor-free air used to dilute the odor sample and serve as the blanks against which the samples are judged. The quality of the dil
48、ution air must be judged to be odor-free by all panel members and the panel moderator. A typical procedure for obtaining odor-free air is to filter it through a charcoal filter. 4.3.1.4.2 Dilution Factor (D). The dimensionless factor based on the ratio of sample flow of an odorous substance into the
49、 total flow of a non-odorous substance is introduced into the test chamber. Flows are usually measured in Liter per minute (L/minute). & =&EHQPEKJ=ENBHKS4=PA +5=ILHA=ENBHKS4=PA5=ILHA=ENBHKSN=PA Where: flow rate = Liter per minute (L/minute) to the sniff ports 4.3.1.4.3 Dose Response Function. The relationship between odor concentration and intensity
