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Describe effluent disinfection, and critical points
Level
5
Credits
4
Purpose
People credited with this unit standard are able to: describe the equipment
used for, and impacts on pathogen of, disinfection methods used in
wastewater effluent treatment; and identify critical points of disinfection
processes, adverse effects, preventive actions, and corrective actions.
Subfield
Water Industry
Domain
Wastewater Treatment
Status
Registered
Status date
19 September 2008
Date version published
19 September 2008
Planned review date
31 December 2013
Entry information
Open.
Replacement information
This unit standard replaced unit standard 19186.
Accreditation
Evaluation of documentation and visit by NZQA, industry
and teaching professional in the same field from another
provider.
Standard setting body (SSB)
Primary Industry Training Organisation
Accreditation and Moderation Action Plan (AMAP) reference
0179
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
Definitions
Critical points – points in a process or in equipment where failure to function correctly can
lead to adverse affects which may affect the treatment process or other processes in the
treatment plant.
Effluent – treated wastewater.
Wastewater – the used water from domestic, commercial, and industrial activities which
contains contaminants such as nutrients, organic matter, and micro-organisms; and
excludes stormwater.
 New Zealand Qualifications Authority 2016
24939 version 1
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Organisational procedures – instructions to staff, and procedures which are documented in
memo or manual format and are available in the workplace. These requirements include
but are not limited to – site specific requirements, manufacturers’ specifications, product
quality specifications, and legislative or regulatory requirements.
Elements and performance criteria
Element 1
Describe the equipment used for, and impacts on pathogen of, disinfection methods used
in wastewater effluent treatment.
Performance criteria
1.1
The process of ultraviolet disinfection is described in terms of the equipment
used, and impacts on pathogens.
Range
1.2
equipment includes but is not limited to – lamp types;
impacts on pathogens – effluent clarity, DNA disruption,
photoreactivation.
The process of disinfection by chlorination is described in terms of the
chemicals and equipment used, and impacts on pathogens.
Range
chlorine sources and forms, residual effects, dechlorination.
1.3
Disinfection by chlorination is described in terms of the methods for monitoring
the performance of equipment for control of indicator organisms.
1.4
The results of monitoring are described in terms of the adjustments that may be
carried out.
Element 2
Identify critical points of disinfection processes, adverse effects, and preventive and
corrective actions.
Performance criteria
2.1
The critical points in disinfection are identified in accordance with organisational
procedures.
2.2
The adverse effects at each critical point are identified in terms of the causes or
the events leading to their occurrence.
2.3
The preventive and corrective actions for problems or events related to each
adverse effect are identified.
 New Zealand Qualifications Authority 2016
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Please note
Providers must be accredited by NZQA, or an inter-institutional body with delegated
authority for quality assurance, before they can report credits from assessment against
unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be accredited by NZQA before they can register
credits from assessment against unit standards.
Accredited providers and Industry Training Organisations assessing against unit standards
must engage with the moderation system that applies to those standards.
Accreditation requirements and an outline of the moderation system that applies to this
standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The
AMAP also includes useful information about special requirements for organisations
wishing to develop education and training programmes, such as minimum qualifications for
tutors and assessors, and special resource requirements.
Comments on this unit standard
Please contact the Primary Industry Training Organisation standards@primaryito.ac.nz if
you wish to suggest changes to the content of this unit standard.
 New Zealand Qualifications Authority 2016