Overview Of USDA HVI Cotton Classification Standards And Qualification .

Overview of USDA HVI CottonClassification Standards andQualification Materials

USDA HVI Cotton ClassificationStandards and Materials for CalibrationUniversal HVI Cotton Calibration Standards– For Strength, Length & Uniformity Index– 2 categories: Long/Strong & Short/Weak– Used for HVI calibration of Length, Strength,Uniformity Index measurements only

USDA HVI Cotton ClassificationStandards and Materials for CalibrationUSDA Pima HVI Calibration Cotton Standards- For Strength, Length & Uniformity Index- 2 Categories: Long/Strong & Short/Weak- Used for HVI calibration of Length, Strength,Uniformity Index measurements only

USDA HVI Cotton ClassificationStandards and Materials for CalibrationUniversal HVI Micronaire Cotton CalibrationStandards– 2 categories: High (Au) & Low (Gu)– Used for HVI calibration for Micronairemeasurement only

USDA HVI Cotton ClassificationStandards and Materials for CalibrationHVI Color Calibration Tiles– Instrument specific calibration tool, not a standard– Set of five tiles– Used for HVI calibration of color Rd and b

USDA HVI Cotton ClassificationStandards and Materials for CalibrationTrash Calibration Tile– Full patterned tile– Instrument specific calibration tool, not a standard– Used for HVI calibration of trash percent area andtrash particle count

USDA HVI Cotton Classification Standards andMaterials for Annual Qualification8x8 Evaluation Cottons For Strength, Length & Uniformity Index 8 categories covering Upland Length/Strength range- Categories:8x8 – 318x8 – 328x8 – 338x8 – 348x8 – 358x8 – 368x8 – 378x8 – 38 Used for qualification of HVI testing level for Length,Strength, Uniformity Index on each HVI instrument

USDA HVI Cotton Classification Standards andMaterials for Annual QualificationInternational Calibration Cotton Standards- For Micronaire only (6 types covering range)- Types: Am, Gm, Cm, Im, Dm, Bm- Used for qualification of HVI testing level formicronaire on each HVI instrument

USDA HVI Cotton Classification Standards andMaterials for Annual QualificationUniversal HVI Cotton Color Standards– For Rd/ b Color– 12 cotton samples representing broad color rangewith standard reference values for Rd/ b– Used for qualification of HVI testing level for Rdand b on each HVI instrument

USDA HVI Cotton Classification Standards andMaterials for Annual QualificationUSDA HVI Trash Standards– For trash percent area and trash particle count– 12 images of cotton samples under glassrepresenting broad trash range with standardreference values percent area and particle count– Used for qualification of testing level for percentarea and particle count on each HVI instrument

Production of HVI ClassificationStandards and QualificationMaterials

Production of StandardsPrepared Annually:200 Sets of Color Tiles200 Trash Tiles100 Color Check Boxes50 HVI Trash Standards20,000 kg of Cottonfor Calibrating HVI Length,Strength, Uniformity andMicronaire Prepared Annually

Production of HVI Cotton Standards All USDA HVI cotton calibration standards traceableto USDA master reference cottons Bales selected based upon USDA classification datafor potential calibration standard Values established through intense testing processes

Production of HVI Cotton StandardsValue Establishment Process Selected bales tested by minimum of 6 HVIinstruments in multiple labs Minimum of 120 test repetitions for each bale toestablish values Bale results must meet strict level and variabilityguidelines to be approved as a standard

Production of HVI Color/Trash Materials USDA HVI color and trash standards traceable toUSDA master reference cottons. USDA color and trash calibration materials traceableto USDA master reference cottons. Values established using master colorimeter/ mastertrashmeter

Production of HVI Color/Trash MaterialsValue Establishment Process Each tile/ cotton tested for 4repetitions at 4 orientations Measurements for each tile/cottonmust meet allowable variabilitytolerances Values established based on theaverage of the 4 measurements Established values are verified

Utilization of Testing Tolerances

Understanding the Nature ofHVI DataImportant Points:- HVI data is statistical in nature- Even the best HVI data has an accepted level ofvariability (error)- Statistical tolerances are required in all areas ofHVI data handling and use- Examples where tolerances are used on HVI data:- Calibration, Qualification, QA, Round Testing, Marketing,Mill laydowns, etc.

Utilization of Testing Tolerances What is a testing tolerance?– Range of acceptable error Why are tolerances needed?– Inherent variability of cotton– Inherent variability of instrument Tolerances vary for testing functions based onthe number of test repetitions

Utilization of Testing Tolerances USDA maintains multiple levels of testingtolerances.– Calibration– Annual Qualification– Retests

Utilization of Testing TolerancesCalibration Tolerances Purpose:– Establish accurate instrument testing level Most restrictive testing tolerance Calibration verification based on 12 combrepetitions for length, strength, uniformityindex

USDA Testing TolerancesCalibration– Micronaire– Strength– Length– Uniformity– Color Rd– Color b– Trash Area– Trash Particle Count0.100.500.0070.700.400.400.055.00

Utilization of Testing TolerancesAnnual Qualification Tolerances Purpose:– Evaluates precision and accuracy based onmultiple reference cottons with established valuesand low standard deviations Based on 8 repetitions per standard cotton/qualification material

USDA Testing TolerancesAnnual QualificationMean MicronaireStrengthLengthUniformityColor RdColor 0120.800.700.30

Utilization of Testing TolerancesRetest Tolerances Purpose:– Evaluates range of data between two sides ofindividual cotton samples Based on comparison of data collected foreach side of the sample (i.e. comb to combdata comparsion)

HVI Testing TolerancesRetests– Strength– Length– Uniformity– Color Rd– Color b– Trash Area– Trash Particle Count5.00.0755.07.02.00.5050

Overview of USDA PhysicalClassification Standards

Universal Grade Standards15 physical standards10 descriptive grades5 below grade

Universal Grade Standards7 of the 15 physicalgrade standardsserve as standardsfor both color andleaf

Universal Color & Leaf Grade edGood Middling11* 1213----Strict Middling21* 2223*2425Middling31* 3233*34*35Strict Low Middling41* 4243*44*--Low Middling51* 5253*54*--Strict Good Ordinary61* 6263*----Good Ordinary71* --------Below Grade8182838485Physical Standards for color grade. All others are descriptive. Physical Standards for leaf grade.*

Grade Standards Production ProcessGeneral Information Physical Grade Standards are valid from July 1 through June 30of each year– Cotton changes color over time, the color accuracy of thecottons in grade standards diminishes with age– Inevitable loss of integrity with repeated use USDA, AMS, Cotton Division produces 3000 Universal Uplandand 240 Pima boxes each year in to supply the demands ofthe domestic and international cotton industry.

Grade Standards Production ProcessStandard represents bottom range of color142356

Grade Standards Production ProcessAssembling the Practical Forms– Select up to 6 bales per grade standard– Selections based on appearance and color chart readings

Grade Standards Production ProcessProduction of Practical Forms

Interpretation of Universal Grade StandardsLeaf grading Official level is onlyrepresented in thewhite grade standards Each “biscuit” withinthe leaf standardrepresents themaximum amount ofleaf contained withinthe grade

Interpretation of Universal Grade StandardsColor Grade Standard represents the bottom range of colorwithin each grade1 2 34 5 6

USDA HVI Cotton Classification Standards and Materials for Calibration Universal HVI Cotton Calibration Standards -For Strength, Length & Uniformity Index -2 categories: Long/Strong & Short/Weak . Selected bales tested by minimum of 6 HVI instruments in multiple labs Minimum of 120 test repetitions for each bale to