1. Prepare for trial batch mixing
   • Identify the job, materials, appropriate procedures and safety requirements
   • Record description of the job to be undertaken, compare with specification and report any variations
   • Select and prepare tools, equipment and materials in accordance with job requirements
   • Confirm the properties and quantities of materials to be used
   • Confirm that the required materials are available and ready for use
2. Mix trial batch for evaluation
   • Measure out quantities of materials ready for mixing
   • Mix the materials according to established procedures
   • Discharge the mixture ready for inspection and testing according to established procedures
   • Record details of the mix and any observations according to established procedures
3. Evaluate properties of the mixture by inspection and standard test methods
   • Obtain representative samples of the mix for testing
   • Perform specified tests according to established procedures
   • Handle and transport samples in accordance with established procedures
   • Label samples and record details in accordance with established procedures
4. Clean equipment and dispose of materials
   • Clean mixing, measuring, sampling and testing equipment after use
   • Return unused materials to storage
   • Dispose of excess materials safely and ethically
5. Maintain records
   • Record data in accordance with established procedures
   • Maintain equipment records in accordance with established procedures
   • Maintain confidentiality of enterprise information
6. Maintain a safe work environment
   • Use established safe work practices and personal protective equipment to ensure personal safety and that of other laboratory personnel
   • Minimise the generation of wastes and environmental impacts
   • Ensure safe disposal of laboratory and hazardous wastes
   • Clean, care for and store equipment and reagents as required.

The Evidence Guide describes the underpinning knowledge and skills that must be demonstrated to prove competence

Critical aspects of competency

Competency must be demonstrated in the ability to perform consistently at the required standard In particular assessors should look to see that the candidate

calculates batch quantities concentrations and other relevant parameters

follows standard operating procedures

measures quantities accurately

takes representative samples

identifies and describes materials accurately

handles and transports samples correctly

records sampling and testing information

uses tools and equipment effectively and efficiently

observes interprets and reports atypical situations

communicates problems to appropriate personnel

records and communicates work results

works safely

interprets information from materials safety data sheets

Underpinning knowledge

Competency includes the ability to apply and explain

the properties of mixing materials and how they affect the properties of the final product

hazards involved with materials and equipment involved

measurement of mass and volume

basic calculations involving SI units proportion ratio and percentage

representative sampling

uses of various materialsenterprise products

basic testing methods for relevant materials

enterprise traceability requirements

relevant health safety and environment requirements

Assessment context and methods

This unit of competency is to be assessed in the workplace or simulated workplace environment

The following assessment methods are suggested

analysis of trial batches prepared by the candidate over a period of time to ensure accurate and consistent work is obtained within required timelines

inspection of workplace documentation completed by the candidate

feedback from peers and supervisors

use of suitable simulation andor a range of case studiesscenarios

In all cases practical assessment should be supported by questions to assess underpinning knowledge and those aspects of competency which are difficult to assess directly Questioning techniques should suit the language and literacy levels of the candidate

Interdependent assessment of unit

This unit of competency may be assessed with

PMLSAMPA Handle and transport samples or equipment

PMLSAMP302A Handle and transport samples or equipment

PMLSAMPB Prepare representative samples in accordance with a sampling plan

PMLSAMP400B Prepare representative samples in accordance with a sampling plan

PMLTESTB Perform basic tests

PMLTEST300B Perform basic tests.

Resource implications

Resources may include

standard facility with appropriate tools equipment and materials

enterprise procedures MSDS product formulationspecifications

This competency in practice

Construction materials

A laboratory assistant works for a concrete manufacturer A client requires concrete for a specific project that cannot be supplied using existing standard mixes The manufacturer must use special aggregates and cement to meet the durability and strength specifications for the project The laboratory manager obtains quantities of the materials for evaluation purposes The assistant tests the aggregates to determine their grading properties From these results heshe designs a mix to satisfy the project specifications using a standard design method The mix requires the use of pozzolanic materials and admixtures that were obtained from the suppliers

The manager provides the assistant with the batch quantities required to produce one cubic metre of concrete To test the mix design the assistant will produce a litre batch in the laboratory Shehe calculates that this quantity will provide sufficient material for the required tests without undue waste Shehe calculates the quantity of each material required for the trial batch The assistant selects and prepares the tools and equipment shehe needs to mix sample and test the concrete Shehe wears overalls safety boots and glasses and uses a barrier cream Shehe measures out the quantities required for the trial batch charges the mixer and allows it to mix for the specified time Shehe then discharges the concrete onto a suitable surface Shehe checks its slump cohesiveness and air content recording the data on standard enterprise forms The manager inspects the concrete and decides that it is oversanded and has excessive slump Shehe adjusts the batch quantities and draws up amended values Shehe disposes of the excess concrete and cleans the equipment and tools

Shehe then mixes a new batch using the amended figures This process continues until the manager is satisfied with the concrete quality Shehe then mixes a larger batch so that shehe can prepare specimens for testing its hardenedstate properties

Key Competencies

The seven key competencies represent generic skills considered for effective work participation The bracketed numbering against each of the key competencies indicates the performance level required in this unit These are standalone levels and do not correspond to the Australian Qualifications Framework AQF

Level represents the competence to undertake tasks effectively

Level represents the competence to manage tasks

Level represents the competence to use concepts for evaluating and reshaping tasks

The range of variables relates to the unit of competency as a whole. It allows for different work environments and situations that will affect performance.