Resources

AWTA Ltd Corporate Brochure

This brochure provides an overview of AWTA Ltd as a whole and explains the roles of the various divisions which make up the AWTA Group.

AWTA is the largest wool testing organisation in the world. The AWTA group is comprised of three operating divisions in Australia (AWTA Raw Wool, AWTA Product Testing and Agrifood Technology), its wholly owned subsidiary NZWTA and its joint venture, JinAo Testing Company. AWTA Ltd continues to expand its service offering into other agricultural and manufacturing markets where independent, high quality and high integrity testing is a vital part of the value chain.

Testing the Woolclip

This brochure has been designed to provide a comprehensive summary of the major services AWTA provides to the wool industry and descriptions of the processes used to achieve test results. The processes dicussed include:

• Presale Test Certificate procedure
• Yield measurement
• Major Vegetable Matter types
• Fibre Diameter measurement
• Staple Length & Strength measurement
• Colour measurement
• Fleece measurement
• Test certificates & reports

Laserscan Technology

This brochure contains a detailled discussion of the Sirolan Laserscan equipment used by AWTA for the determination of Mean Fibre Diameter. It reviews the IWTO methods that are followed during the measurement and certification process and explains in general terms how the equipment measures wool fibres. The main topics are:

• Measurement
• Precisions
• Interferences
• Calibration
• Processing
• Benefits
• Measuring finess characteristics of wool fibres
• The Laserscan instrument
• Benefits to wool growers & processors

Vegetable Matter in Australian Wool

This booklet provides a useful reference for the identification of the major Vegetable Matter types which occur in Australian wool. The need for correct identification and standard nomenclature descriptions of vegetable matter is important and becomes even more so if the industry is to move to a system of selling based on measurement and standardised descriptions alone.

The 3 broad categories of VM Type disucced in this handbook, coded simply B, S and H, are defined as follows:are sometimes questioned..

• Burrs – clover & medic burrs
• Seeds – seed material, shive, grasses & thistles
• Hard-Heads – hard heads (bean burrs), sticks & twigs

The VM types are described in this booklet as either B, S or H, as appropriate.

Objective measurement is an integral part of the preparation, marketing and processing of Australian wool.Nearly all Australian wool is tested for Yield, Vegetable Matter Base and Mean Fibre Diameter prior to sale and/or prior to export. An increasing proportion is also tested for Mean Staple Length and Mean Staple Strength. Scoured and carbonised wool is normally tested for Regain (moisture content). However, a significant number of scoured and carbonised lots are also tested for Yield and Mean Fibre Diameter.

This handbook is designed to provide members of the wool industry with details of the technical basis to Objective Measurement and the procedures for many of the common calculations. The information included is largely drawn from, or based upon, the relevant IWTO Test Methods and Regulations and Australian Standards.

The key features of the booklet are:

• Calculation procedures and terminology are outlined for various Test Certificates
• Sections on the precision of testing and retesting are included. These sections describe procedures available for improving the precision of a test result and the procedures followed by Test Houses when a retest is initiated
• Core Test interyield conversion tables previously published in a separate booklet are included
• A bareme for the calculation of theoretical HAUTEUR from raw test data according to the formula described in the report on trials evaluating additional measurements 1981-88, December 1988 (TEAM) has been included

This handbook, first published in September 1990 will not be reprinted. Copies of the latest issue of the handbook are still available and can be obtained from the nearest AWTA Raw Wool office.

Conversion Tables

The AWTA Wool Testing Handbook contains examples of calculations associated with IWTO Certificates, conversion tables for a number of Yields and tables for calculating Hauteur, based on the TEAM 2 Formula from Staple Measurements.

The conversion tables have been extracted from the Handbook and are available for download. These tables provide for conversions between yields as well as calculation of TEAM Hauteur from the Yield, Micron and Staple Measurement data.

A separate download is available that contains conversion tables and formulae for Scoured Yield at 16%, which were not included in the original publication.

Find out more:

With the universal use of Test Certificates to define the specification of a wool trading contract, the accuracy and precision of the test results are sometimes questioned. This is particularly so as new measurements are introduced and there is no relaxation of commercial specifications in contracts.For the new generation of wool market traders, this is an update of earlier reports (reference 1,2,3) on this subject. It provides information to minimise the potential conflicts that can arise between the commercial wool trading requirements and the technical limitations of IWTO Test Methods and Regulations.

It discusses issues such as accuracy, bias and precision, what factors affect these charateristics and how they are relevent to wool testing. The relationship between check-tests and re-tests is also explained.