Required skills

Required skills include

establishing client needs for routine and nonroutine samples

interpreting client requests test methods and procedures accurately

selecting appropriate UVVISNIR techniques and installing instrument accessories

selecting adapting and modifying standard test methods for unknown samples

preparing samples and standards and optimising procedures and equipment to suit sampletest requirements

setting up starting up and shutting down equipment

checking the calibrationqualification status of equipment

selecting configuring checking and optimising instrument subsystems

performing routine instrument maintenance and replacement of consumables

obtaining valid and reliable data

calculating analyte concentrations with appropriate accuracy precision uncertainty and units

recognising atypical dataresults and troubleshooting common analytical procedure and equipment problems

recording and reporting dataresults using enterprise procedures

maintaining security integrity and traceability of samples and documentation

assessing risks applying specified control measures and working safely

minimising waste ensuring safe collection and disposal

applying relevant principles of good laboratory practice GLP procedures

maintaining technical knowledge by accessing journals technical updates suppliers product notes and test methods

Required knowledge

Required knowledge includes

criteria for determining which UVVISNIR technique eg cell accessory is best suited to which type of sample eg gas liquid bulk solid fibre film and small quantity

sample preparation procedures including specialised techniques such as

handling unstablehazardous chemicals and samples fragilelabile biological material

dilution without causing chromaphoric shifts

filtration or centrifugation to remove particulates

prevention of personal contamination of samples by exposure to analyst

cleaning andor handling of optical elements

cleaning techniques and handling of cells and flow cells

cleaning of reflectance standards and liquid standards

alignment techniques for source mirrors and accessories

UVVISNIR spectroscopic terms and concepts such as

excitation absorption absorbance transmittance reflectance and fluorescence

electronic transitions during absorptionfluorescence and relationship to chemical properties interference and quenching

concepts such as Beers Law Bouguer or Lamberts Law and molar absorptivity

deviations from Beers Law polychromatic radiation and chemical reactions

chromaphores and auxochhromes

conjugation effects in organic molecules

pH effects in ionised samples

solvent effects

spectral resolution spectral bandwidth and linear dispersion

limit of detection limit of quantitation and their application to quality control procedures

derivative spectra

multicomponent analysis

analysis of reaction kinetics

calculations and data processing involving

concentration and dilution

spectral matching

first and higher derivatives of spectra

multicomponent quantitation

operation construction selectivity typical applications troubleshooting and routine maintenance of UVVISNIR systems including details such as

sources such as deuterium and tungsten filament

monochromators such as prisms gratings and filters

sample holders such as quartz glass and plastic cuvettes cells and fibre optic dip probes

detectors such as photomultipliers photodiode diode arrays charge coupled devices and semiconductor devices for NIR eg PbS and InGaAs

accessories that extend capabilities such as autosamplers thermostat controlled cell holders multicell transports and diffuse and specular reflectance units

calibration procedures for

accuracy of wavelength and absorbance using hydrogendeuterium holmium oxide glass filters and holmium perchlorate solution

stray radiation using recommended liquids for each spectral range

photometric accuracy using potassium dichromate solution

zero absorbance baseline flatness

sources of spectral interferences such as

particulates

fluorescence from heavy metals

interfering chromaphores

masking by chelating agents

computer control software for operating and optimising instrument

procedures for optimising instrument performance such as

alignment of subsystems eg source mirror and accessories

adjustment of slit and signalnoise ratio to obtain satisfactory spectral resolution

use of manualcomputer calibration charts andor standards to identify and quantify analytes such as

external calibration with or without internal standardisation

multicomponent analysis

semiquantitative analysis

library searching for spectral matching

derivative spectrum analysis

calculation steps to give results in appropriate units and precision

troubleshooting and maintenance procedures recommended by instrument manufacturer

enterprise andor legal traceability requirements

relevant health safety and environment requirements

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

interpret client requests test methods and procedures accurately

replace standard UVVISNIR instrument consumables such as lamps and purge gases

install UVVISNIRaccessories such as optical fibre probes microscopes and reflectance units

safely set up start up and shut down instrument using enterprise procedures

prepare samples and calibration standards in accordance with test method

check calibrationqualification status of equipment

optimise instrument subsystems and procedures and equipment to suit sampletest requirements

operate equipment to obtain valid and reliable data

use software to identify analytes and calculate concentrations with appropriate accuracy precision and units

recognise atypical dataresults

troubleshoot common analytical procedure and equipment problems

record and report dataresults using enterprise procedures

maintain security integrity and traceability of samples and documentation

follow OHS procedures and principles of GLP

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

MSLA Evaluate and select appropriate test methods and procedures

MSL976003A Evaluate and select appropriate test methods and procedures

MSLA Contribute to the validation of test methods

MSL977003A Contribute to the validation of test methods

MSLA Develop or adapt analyses and procedures

MSL977004A Develop or adapt analyses and procedures.

Resources may include

laboratory with specialised analytical instruments

laboratory reagents and equipment

SOPs and test methods

Method of assessment

The following assessment methods are suggested

review of test dataresultscalibration graphs obtained by the candidate over time to ensure accuracy validity precision and timeliness of results

inspection of results and technical records eg maintenance schedules and quality control logbooks completed by the candidate

observation of candidate using UVVISNIR instruments to measure analytes

feedback from clients peers and supervisors

oral or written questioning of relevant UVVISNIR spectroscopy concepts chemical principles underpinning sample preparation and separation of species instrument design and optimisation analytical 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

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 andor 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 workplacesetting

Forensic science

A forensic science team is examining some fibre samples taken from a crime scene and a suspect After a careful microscopic examination of the two sets of samples one technician determines that both contain blue polyester fibres Because of the problems associated with extracting dyes from fibres the team decides to first use a nondestructive analytical technique This involves obtaining the UVVIS absorption spectra of single fibres using microspectrophotometry Each fibre is mounted between a quartz slide and cover slip and examined in transmission The laboratorys instrument enables the technician to obtain a several spectra from a x spot for a wavelength range of nm to nm The repeat spectra for each fibre are first compared for internal consistency by overlaying the spectra in pairs The spectra for each fibre are then compared with those obtained for the other fibres and with the reference spectra for a large number of known blue polyester fibres in an international spectral library To provide enhanced discrimination derivative spectra are used to reveal subtle inflections and changes of gradient in the broad convoluted absorption peaks However because of the spatial variations in dye uptake within any one fibre these derivative spectra could not be relied on to provide conclusive identification The team then attempted to measure each fibres birefringence using a polarising microscope and employed a variety of FTIR transmission and reflectance techniques to shed more light on the chemical properties of the two sets of fibres

Food processing

A laboratory technicians manager asks himher to determine the concentration of Vitamin C in a sample of clear apple juice The technician is very familiar with the analytical methods used for determining Vitamin C in bulk pharmaceutical preparations but soon realises that these methods do not give a reliable result in this case Heshe considers alternative spectroscopic methods The technician is aware that the laboratory has a modern UVVIS spectrometer with an advanced spectrum calculator capable of producing up to th order derivative spectra After finding a suitable method the technician determines the Vitamin C content by using the instruments derivative capability to produce sharp peaks and overcome the broad UV absorption bands usually obtained with this kind of sample

Codes of practice

Standards, codes, procedures and/or enterprise requirements

UV/VIS/NIR instruments and techniques

Testing that uses UV/VIS/NIR spectroscopy

Presumptive tests

Sample and standard preparation

Pre-use, calibration and safety checks

Instrumental parameters

Common analytical procedure problems and remedies

Common equipment problems

Hazards

Addressing hazards

Occupational health and safety (OHS) and environmental management requirements