Elements and Performance Criteria

RANGE STATEMENT
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 ISO 10005:2006 Quality management systems - Guidelines for quality plans
AS/NZS ISO 10012:2004 Measurement management systems - Requirements for measurement processes and measuring equipment
AS/NZS ISO 9000 Set:2008 Quality management systems set
ISO 5725 Accuracy (trueness and precision) of measurement methods and results
ISO/IEC Guide 98-3:2008 Uncertainty of measurement-Part 3 Guide to the expression of uncertainty in measurement (GUM)
Eurachem/CITAC Guide CG4 Quantifying uncertainty in analytical measurement
Australian code of good manufacturing practice for medicinal products (GMP)
enterprise quality manual, customer quality plan
equipment manuals and warranty, supplier catalogues, handbooks
Eurolab technical report
NATA Accreditation programs requirements
principles of good laboratory practice (GLP)
NATA Technical notes
national measurement regulations and guidelines
Nordtest guide
sampling and test procedures and standard operating procedures (SOPs)
Data
Data may:
be recorded on worksheets or entered into spreadsheets or databases linked to information management systems
include the results of tests, measurements and analyses
Calculations
Calculations may be performed with or without a calculator or computer software, such as spreadsheets, databases and statistical packages
Statistical analysis
Statistical analysis may include the use of:
standard deviation, standard deviation of the mean, histograms and frequency plots
probability and normal probability plots
control charts
regression methods for calibration, linearity checks and comparing analytical methods
analysis of variance (ANOVA)
data acceptability tests, such as T and F
Records
Records may include information associated with:
purchase of equipment and materials and service records
manufacturer's datasheets
calibration reports
history of calibration and test results
Uncertainty components
Uncertainty components may include:
calibration uncertainty
instability or drift in the calibrated instrument
repeatability of the results
resolution or readability of the instrument
environmental influences such as temperature, air pressure, humidity, vibration, electrical noise and gravity
reference material uncertainty
factors arising from using an instrument under a different operating environment or procedures (e.g. orientation of a transducer and immersion depth of a temperature probe)
reproducibility of quality control data
Confidence level
The most common confidence level is 95% in accordance with the National Measurement Act, 1960. However, some applications require a higher level of confidence
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

EVIDENCE GUIDE
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:
prepare a realistic uncertainty budget that is appropriate for the application
fully document the uncertainty budget
report results and uncertainties in the required formats.

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:
MSL904001A Perform standard calibrations
MSL905001A Perform non-standard calibrations.
Resources may include:
data sets and records
test methods and description of test setup
computer and relevant software or laboratory information system
relevant workplace procedures.

Method of assessment
The following assessment methods are suggested:
review of data worksheets, calculations, computer files (such as spreadsheets and databases), statistical analysis, graphs and/or tables prepared by the candidate
questions to assess understanding of relevant procedures, trends in data and sources of uncertainty
review of reports prepared by the candidate
feedback from supervisors and peers regarding the candidate's ability to estimate uncertaintyin accordance with 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 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
Production workers in a water meter manufacturing company are required to batch test water meters. Twenty meters are connected together and tested at the same time using a test rig that collects the water in a tank that sits on top of a weighing instrument. The company's production technician needs to ensure that each water meter meets its maximum permissible error and that all measurements have a maximum permissible uncertainty that is below that specified by the regulator. The technician needs to consider the calibration uncertainty of the weighing instrument, any drift in it over time, the resolution of the meters under test and other factors relating to the temperature of the water, its effect on its density and the buoyancy correction for the weighing instrument.
There are a number of corrections that need to be applied in order to achieve an uncertainty less than the maximum permissible uncertainty. Production workers enter readings from the meters into a palm-held device. This data is then downloaded to a computer which uses a spreadsheet program to make the required corrections, tabulate the readings, calculate the uncertainties and determine compliance of each meter with the regulations and produce a report. Uncertainty components may change for different models of water meters that have different flowrates, readability and minimum deliveries. To cope with this, the technician's spreadsheet program has 'look-up' tables for these components according to the water meter model. Once this system was setup there is no ongoing overhead costs for uncertainty estimation. The calibration uncertainty may have to be updated when the weighing instrument is recalibrated. Estimating uncertainties have highlighted which uncertainty components have the biggest effect on the final uncertainty. This tells the technician which components to focus on and which have little effect.
Chemical
A consulting laboratory analyses beef fat for a meat export company to determine the concentration of the pesticide residue Dieldrin prior to export. The maximum residue limit for Dieldrin in beef fat is 0.2 mg/kg. The technician analyses the sample using a validated gas chromatography (GC) method. To estimate the measurement uncertainty of the analysis he/she needs to take into account such things as the:
uncertainty from the GC calibration
uncertainty associated with the reference materials used
homogeneity of the sample
calibration of the glassware used for the analysis
the repeatability
reproducibility of the method
uncertainty of the method recovery.
The technician calculates a result and uncertainty of 0.19 ± 0.02 mg/kg. The reported uncertainty suggests to the meat export company that the concentration of Dieldrin in the meat products could be above the residue limit. They can now make informed decisions about whether to sell the meat or not and possibly avoid exporting meat with excessive levels of pesticide residue which could cost the exporter millions of dollars in lost revenue.
Calibration
Technicians in a commercial calibration laboratory routinely calibrate digital multimeters -including 3½ digit hand-held multimeters and high accuracy 6½ digit bench mounted multimeters. From experience, they know that there are some uncertainty components common to each calibration such as the:
uncertainty of the calibration of their reference instrument (a calibrator)
drift over time of their reference which they establish from its yearly calibrations over the last 5 years
repeatability of their measured results at each test point from which they calculate a standard deviation of the mean
resolution of the multimeter being calibrated.
Because of the higher accuracy of the 6½ digit multimeter, the technicians know that for these instruments they must also consider additional uncertainty components such as the input impedance of cables together with thermal and capacitive effects. (These components may be insignificant in terms of the accuracy of a 3½ digit multimeter). The uncertainty estimation and the rigour required relates to the accuracy required. The tolerance in electrical calibrations is typically the manufacturer's specification and the uncertainty needs to be smaller than that so that they can decide whether an instrument is within specification. A 4:1 tolerancetouncertainty ratio (TUR) is typical. The technician's thorough understanding of uncertainty estimation enables the laboratory to optimise their measurement effort to ensure they achieve the 4:1 ratio in an efficient manner. The laboratory has NATA accreditation which lists not only what calibrations they can perform, but their best accuracy ('least uncertainties of measurement'). As part of the process of gaining accreditation they need to submit to NATA for review their uncertainty estimations to justify the uncertainties that appear in their scope of accreditation and which they report on appropriate instruments.