The Evidence Guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

Critical aspects for assessment and evidence required to demonstrate competency in this unit

Assessors should ensure that candidates can:

accurately interpret enterprise procedures or standard methods

complete all tests within the required timeline without sacrificing safety, accuracy or quality

demonstrate close attention to the accuracy and precision of measurements and the data obtained

maintain the security, integrity and traceability of all samples, data/results and documentation.

Context of and specific resources for assessment

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

This unit of competency may be assessed with:

MSL922001A Record and present data.

Resources may include:

standard laboratory equipped with appropriate equipment standards and materials

enterprise procedures and standard methods, and equipment manuals

MSDS.

Method of assessment

The following assessment methods are suggested:

review of the quality of test data/results achieved by the candidate over time

inspection of records and workplace documentation completed by the candidate

feedback from peers and supervisors

observation of the candidate performing a range of basic tests

oral or written questioning to check underpinning knowledge of test procedures.

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.

Where applicable, reasonable adjustment must be made to work environments and training situations to accommodate ethnicity, age, gender, demographics and disability.

Access must be provided to appropriate learning and/or assessment support when required.

The language, literacy and numeracy demands of assessment should not be greater than those required to undertake the unit of competency in a work like environment.

This competency in practice

Industry representatives have provided the case studies below to illustrate the practical application of this unit of competency and to show its relevance in a workplace setting.

Manufacturing

Standard testing methods may be viewed as legal requirements that must be followed to ensure that a product manufactured in a chemical plant meets the specification by which it is sold to the customer. Technical assistants perform tests in a quality control laboratory to ensure that material meets legal requirements and the material is safe and effective in use. Peroxides may be present in ether as a result of light-catalysed air oxidation. Peroxides are toxic and can give rise to mixtures which are explosive when distilled. Technical assistants test ether to ensure that the level of peroxide is within acceptable limits. The test is done by shaking ether with a solution of potassium iodide. After standing for 30 minutes in the dark the yellow colour of the aqueous phase, due to the liberation of iodine, must not be more intense than a prepared standard solution. These tests ensure the quality and safety of the ether.

Food processing

A snack food company produces a range of high quality, impulse purchase snack foods. Some of these products are moisture and/or oxygen sensitive and are therefore packaged in multi-layer flexible packaging to provide optimum shelflife. The packaging must also be able to withstand the rigours of the production and distribution process. While the packaging is purchased to meet the shelflife and distribution specifications, the quality assurance program requires the periodic evaluation of the packaging materials against these specifications. A laboratory assistant uses standard methods to test the tearing resistance, bursting strength, impact resistance and permeability and/or leakage of the snack food packaging. Tests are also conducted on aspects of the manufacturing process that can affect shelflife. These tests involve the measuring of the heat-seam strength and the sealing performance of the closure process. The test results are recorded by the laboratory assistant to verify the conformance of the materials to the supplier specifications and of the process to the manufacturing specifications. The assistant reports any anomalies or non-conformances to the appropriate personnel.

Construction materials testing

A technician performs an Aggregate Stripping Test (AS 1141.50) and enters the results in the laboratory's information management system (LIMS). The resulting 20-30% stripped values (i.e. 70-80% adhering) indicate a 'fail' result. The technician notes that he has repeated the test and obtained the same 'fail' result. The laboratory manager reviews the results and asks the technician to explain how he performed the test. He describes how he prepared 3-4 mm thick plates of bitumen and binding agent in the mould and then placed 50 small clean pieces of aggregate on top. After treatment in an oven for 24 hours and a 50°C water bath in accordance with the test method, the technician had then carefully pulled out the pieces of aggregate and avoiding any twisting motion. He then estimated the % of bitumen adhering to each of the stones with the expectation that the stripped value would be about 5% (i.e. 95% adhering). The manager is satisfied that the technician has performed the test in accordance with the method and suggested that he now re-run the test with a known aggregate as a control. This test gives a stripped value of 5-7% (i.e. 93-95% adhering). The manager is now sufficiently confident of the laboratory's results to sign and issue the test report and explain the aggregate's 'test failure' to the client.

Required skills

Required skills include:

interpreting enterprise procedure or standard methods accurately

using safety information, such as material safety data sheets (MSDS) and performing procedures safely

checking test equipment before use

completing all tests within required timeline without sacrificing safety, accuracy or quality

calculating, recording and presenting results accurately and legibly

maintaining security, integrity and traceability of all samples, data/results and documentation

cleaning and maintaining equipment

Required knowledge

Required knowledge includes:

concepts of metrology

the international system of units (SI)

purpose of test

principles of the standard method

pre-use equipment checks

relevant standards/specifications and their interpretation

sources of uncertainty in measurement and methods for control

enterprise and/or legal traceability requirements

interpretation and recording of test result, including simple calculations

procedures for recognition/reporting of unexpected or unusual results

relevant health, safety and environment requirements

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Codes of practice

Where reference is made to industry codes of practice, and/or Australian/international standards, it is expected the latest version will be used

Standards, codes, procedures and/or enterprise requirements

Standards, codes, procedures and/or enterprise requirements may include:

Australian and international standards, such as:

AS ISO 1000-1998 The international system of units (SI) and its application

AS ISO 17025-2005 General requirements for the competence of testing and calibration laboratories

AS/NZS 2243 Set:2006 Safety in laboratories set

Australian code of good manufacturing practice for medicinal products (GMP)

calibration and maintenance schedules

enterprise recording and reporting procedures

equipment manuals

equipment startup, operation and shutdown procedures

MSDS and safety procedures

material, production and product specifications

national measurement regulations and guidelines

principles of good laboratory practice (GLP)

production and laboratory schedules

quality manuals

standard operating procedures (SOPs)

Concepts of metrology

Concepts of metrology may include:

that all measurements are estimates

measurements belong to a population of measurements of the measured parameters

repeatability

precision

accuracy

significant figures

sources of error

uncertainty

traceability

Preparation of samples

Preparation of samples may include:

sub-sampling or splitting using procedures, such as riffling, coning and quartering, manual and mechanical splitters

diluting samples

physical treatments, such as ashing, dissolving, filtration, sieving, centrifugation and comminution

moulding, casting or cutting specimens

Typical tests carried out by laboratory/field assistants

Typical tests carried out by laboratory/field assistants may include:

visual/optical tests of appearance, colour, texture, identity, turbidity, refractive index (alcohol content and Baume/Brix)

physical tests:

density, specific gravity and compacted density

moisture content and water activity

particle size, particle shape and size distribution

chemical tests:

gravimetric

colorimetric

electrical conductivity (EC) and pH

specific ions using dipsticks and kits

nutrients (e.g. nitrates and orthophosphates) using basic kits

ashes, including sulphated ashes

biological/environmental tests:

pH, oxygen reduction potential (ORP), dissolved oxygen (DO) and (EC)

E coli using test kits

surface hygiene/presence of microbes

packaging tests:

tearing resistance, bursting strength and impact resistance

permeability and/or leakage

mechanical tests:

Emerson class

concrete slump

Measurements

Measurements may include:

simple ground surveys

meteorological parameters, such as wind direction/strength, rainfall, maximum/minimum temperature, humidity and solar radiation

simple background radiation survey

production/process parameters, such as temperature, flow and pressure

gas levels in a confined space

Common measuring equipment

Common measuring equipment may include:

dimension apparatus

DO and EC

analogue and digital meters and charts/recorders

basic chemical and biological test kits

dipsticks and site test kits (e.g. HACK)

timing devices

temperature measuring devices, such as thermometers and thermocouples

Hazards

Hazards may include:

electric shock

biohazards, such as microbiological organisms and agents associated with soil, air, water, blood and blood products, and human or animal tissue and fluids

solar radiation, dust and noise

chemicals, such as sulphuric acid, fluorides and hydrocarbons

aerosols

sharps, broken glassware and hand tools

flammable liquids

dry ice and liquid nitrogen

fluids under pressure

sources of ignition

occupational overuse syndrome, slips, trips and falls

manual handling, working at heights and working in confined spaces

crushing, entanglement and cuts associated with moving machinery or falling objects

Enterprise controls to address hazards

Enterprise controls to address hazards may include:

use of MSDS

use of signage, barriers and service isolation tags

use of personal protective equipment, such as hard hats, hearing protection, sunscreen lotion, gloves, safety glasses, goggles, face guards, coveralls, gowns, body suits, respirators and safety boots

use of appropriate equipment, such as biohazard containers and cabinets and laminar flow cabinets

recognising and observing hazard warnings and safety signs

labelling of samples, reagents, aliquoted samples and hazardous materials

handling and storage of all hazardous materials and equipment in accordance with labelling, MSDS and manufacturer's instructions, and enterprise procedures and regulations

cleaning and decontaminating equipment and work areas regularly using recommended procedures

following established manual handling procedures for tasks involving manual handling

Minimising environmental impacts

Minimising environmental impacts may involve:

recycling of non-hazardous waste, such as chemicals, batteries, plastic, metals and glass

appropriate disposal of hazardous waste

correct disposal of excess sample/test material

correct storage and handling of hazardous chemicals

Occupational health and safety (OHS) and environmental management requirements

OHS and environmental management requirements:

all operations must comply with enterprise OHS and environmental management requirements, which may be imposed through state/territory or federal legislation - these requirements must not be compromised at any time

all operations assume the potentially hazardous nature of samples and require standard precautions to be applied

where relevant, users should access and apply current industry understanding of infection control issued by the National Health and Medical Research Council (NHMRC) and State and Territory Departments of Health