Elements and Performance Criteria

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.
Concepts of chemistry may include:
atoms, ions, molecules and compounds
chemical bonding
chemical reactions
acids and bases
oxidation reduction potential (ORP)
Workplace policies and procedures may include:
organisational policies
standard operating procedures
communication and reporting protocols
quality assurance
Relevant legislation may include:
federal, state and local environmental and water quality legislation
occupational health and safety legislation
hazardous chemicals and dangerous goods legislation
Chemical reactions may include:
neutralization and pH buffering
pH correction
calcium carbonate precipitation
coagulation
chemical P removal
iron and manganese removal
sequestering
Functions may include:
disinfectant
oxidant
reductant
sequestering agent
pH correction and buffering
coagulant
flocculant
surfactant
adsorbent
precipitant
catalyst
Chemicals used in the water industry may include:
chlorine
ozone
sodium thiosulphate
sodium hexametaphosphate
activated carbon
hydrated lime
aluminium and iron salts
potassium permanganate
sulphuric acid
Factors influencing the effectiveness of chemical use may include:
pH
ageing
mixing
temperature
concentration
Factors affecting the selection of chemicals may include:
cost
purity
availability
by-product generation
storage and handling requirements
safety requirements
efficiency and effectiveness

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
The candidate should:
perform each task outlined in the elements consistently and in a representative range of contexts required by the enterprise and worksite
meet the performance criteria associated with each element by employing the techniques, procedures, information and resources available in the workplace from those listed in the range statement
demonstrate an understanding of the underpinning knowledge and the application of skills as described in the required skills and knowledge section
Critical aspects for assessment and evidence required to demonstrate competency in this unit
The candidate should demonstrate the ability to:
understand and apply a knowledge of chemical concepts and reactions relevant to water industry processes
describe the range, characteristics and functions of chemicals used in various water industry processes
identify and evaluate the factors influencing the effectiveness of chemicals in specific water industry processes
select appropriate chemicals for specific water industry processes
Context of and specific resources for assessment
Access to the workplace and resources, including:
documentation that should normally be available in a water industry organisation
relevant codes, standards and government regulations
Where applicable, physical resources should include equipment modified for people with disabilities.
Access must be provided to appropriate learning and assessment support when required.
Assessment processes and techniques must be culturally appropriate, and appropriate to the language and literacy capacity of the candidate and the work being performed.
Validity and sufficiency of evidence requires that:
competency will need to be demonstrated over a period of time reflecting the scope of the role and the practical requirements of the workplace
where the assessment is part of a structured learning experience the evidence collected must relate to a number of performances assessed at different points in time and separated by further learning and practice
a decision of competence only taken at the point when the assessor has complete confidence in the person's competence over time and in various contexts
all assessment that is part of a structured learning experience must include a combination of direct, indirect and supplementary evidence
where assessment is for the purpose of recognition (RCC/RPL), the evidence provided will need to be authenticated and show that it represents competency demonstrated over a period of time
assessment can be through simulated project-based activity and must include evidence relating to each of the elements in this unit
In all cases where practical assessment is used it will be combined with targeted questioning to assess the underpinning knowledge. Questioning will be undertaken in a manner appropriate to the skill levels of the operator and cultural issues that may affect responses to the questions, and will reflect the requirements of the competency and the work being performed.