Elements and Performance Criteria

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.
Where reference is made to industry codes of practice, and/or Australian/international standards, it is expected the latest version will be used.
All operations and analytical methods must comply with relevant standards, appropriate procedures and/or enterprise requirements.

These procedures include or have been prepared from
Australian and international standards such as -
AS ISO/IEC 17025 General requirements for the competence of testing and calibration laboratories
ISO 9000 series Quality management and quality assurance standards
AS 2243.2 Safety in laboratories - chemical aspects
AS 2830.1 Good laboratory practice - chemical analysis
codes of practice such as GLP and GMP
material safety data sheets (MSDSs)
National Measurement Act
standard operating procedures (SOPs)
quality manuals, equipment and procedure manuals
equipment start-up, operation and shutdown procedures
calibration and maintenance schedules
data quality procedures
enterprise recording and reporting procedures
production and laboratory schedules
material, production and product specifications.

Routine electrometric techniques may include use of
ion selective electrodes
potentiometric titrations
conductometric titrations
amperometry
polarography.

Tests may include methods for
control of starting materials, in-process materials and finished products
environmental monitoring
therapeutic drug analysis
determination of enzyme activity
routine determination of chemical analytes such as fluoride, nitrate, water hardness, lead, copper, quinine
troubleshooting enterprise processes.

Sample preparation may include
identification of any hazards associated with samples and/or analytical chemicals
grinding, mulling, digestion, dissolving, ashing, refluxing, extraction, filtration, evaporation, flocculation, precipitation, washing, drying, centrifugation
determination of and, if appropriate, removal of any contaminants or impurities.

Common analytical procedure and equipment problems may include
matrix interferences such as formation of complexes
physical damage to electrodes.

Hazards may include
electric shock
biohazards such as microbiological organisms and agents associated with soil, air, water, blood and blood products, human or animal tissue and fluids
chemicals such as-
acids for example, sulphuric, perchloric, hydrofluoric
heavy metals, pesticides
anions for example, fluoride
hydrocarbons for example, phenol, toluene, benzene, mono-aromatics
ammonium persulphide
sharps, broken glassware
aerosols from broken centrifuge tubes, pipetting
flammable liquids and gases
cryogenics such as dry ice and liquid nitrogen
sources of ignition
disturbance or interruption of services.

Addressing hazards may involve
use of material safety data sheets (MSDS)
labelling of samples, reagents, aliquoted samples and hazardous materials
use of personal protective equipment such as gloves, safety glasses, coveralls
use of fumehoods, direct extraction of vapours, gases
use of appropriate equipment such as biohazard containers, laminar flow cabinets, Class I, II and III biohazard cabinets
handling and storage of all hazardous materials and equipment in accordance with labelling, materials safety data sheets and manufacturer's instructions.

Health, safety and environment
All operations to which this unit applies are subject to stringent health, safety and environmental (HSE) requirements, which may be imposed through State or Federal legislation, and these must not be compromised at any time. Where there is an apparent conflict between performance criteria and HSE requirements, the HSE requirements take precedence.
All operations assume the potential hazardous nature of samples and require standard precautions to be applied. Users should access and apply current industry understanding of infection control issued by the National Health and Medical Research Council and State and Territory Departments of Health. All operations are performed in accordance with standard operating procedures.

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:

interprets client request, test methods and procedures accurately
can safety set up and shut down equipment using enterprise procedures
checks calibration/qualification status of equipment
prepares standards and samples appropriately
chooses and optimises procedures and equipment settings to suit sample/test requirements
operates equipment to obtain valid and reliable data
makes approved adjustments to procedures for non-routine samples
recognises atypical data/results
troubleshoots common analytical procedure and equipment problems
applies theoretical knowledge to interpret data and makes relevant conclusions
records and reports data/results in accordance with enterprise procedures
maintains security, integrity and traceability of samples and documentation
follows OHS procedures and GLP.

Underpinning knowledge

Competency includes the ability to apply and explain:

redox and electrical principles and concepts related to instrumentation operation and testing
handling of unstable or hazardous chemicals and samples and/or the fragile/labile nature of biological material
sample preparation procedures
use of various electrometric techniques for qualitative and quantitative analysis
function of key components of the instrument
effects on outputs and results of modifying instrumental variables such as voltage and current ranges
procedure for optimising equipment by changing operation parameters such as drop rate and scan speed
basic procedure and equipment troubleshooting techniques
preparation and use of calibration charts and/or standards
calculation steps to give results in appropriate accuracy, precision and units
enterprise and/or legal traceability requirements
basic equipment maintenance procedures
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:

review of test data/results obtained by the candidate over time to ensure accuracy, consistency and timeliness of results
inspection of test records and workplace documentation completed by candidate
feedback from peers and supervisors
observation of candidate applying a range of routine electrometric techniques
oral or written questioning of chemical principles and concepts, electrometric techniques and enterprise 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. Questioning techniques should suit the language and literacy levels of the candidate.

Interdependent assessment of unit

This unit of competency may be assessed with:

PMLDATA500B Analyse data and report results.

Resource Implications

Resources may include:

standard laboratory equipped with routine electrometric equipment, laboratory reagents and equipment
standard operating procedures (SOPs) and test methods.

This competency in practice
Quality control tests on toothpaste require the monitoring of the soluble fluoride in the product. To analyse a sample, the technician uses an ultrasonic bath to disperse the paste in a buffer which controls ionic strength and pH (known as TISAB). He/she then measures the fluoride content using a fluoride ion-selective electrode which has been calibrated against a range of fluoride in TISAB standards.
A technician routinely analyses effluent samples from a copper smelter for their lead and zinc content using differential pulse polarography. The samples require no pre-treatment other than the addition of solid KCl as electrolyte. The technician programmes the polarograph to analyse multiple samples on a carousel and to perform standard additions automatically by drawing aliquots from a concentrated standard of the two metals.
One of the important quality tests for a wine is its total acidity (principally tartaric acid). Because of the colour of red wine, it is not possible to perform a titration using an indicator for endpoint detection. The technician is required to calibrate a pH electrode and titrate aliquots of the wine to a pH of 8.4 with standardised NaOH. The endpoint pH is the generally accepted one for wines of all types.

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 stand-alone levels and do not correspond to levels in the Australian Qualifications Framework (AQF).
Level (1) represents the competence to undertake tasks effectively
Level (2) represents the competence to manage tasks
Level (3) represents the competence to use concepts for evaluating and reshaping tasks.
Communicating ideas and information
(2)

Collecting analysing and organising information
(2)

Planning and organising activities
(2)

Working with others and in teams
(2)

Using mathematical ideas and techniques
(2)

Solving problems
(2)

Using technology
(3)