24970 version 1
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Optimise and manage chlorine disinfection processes for drinkingwater treatment
Level
5
Credits
8
Purpose
People credited with this unit standard are able to: optimise and manage
chlorine disinfection processes, variables which determine their
effectiveness, design features, the equipment used, methods of application,
safety considerations, and operating issues associated with chlorine
disinfection; and identify critical points, hazards, and preventive and
corrective actions, in chlorine disinfection processes.
Subfield
Water Industry
Domain
Water Treatment
Status
Registered
Status date
19 September 2008
Date version published
19 September 2008
Planned review date
31 December 2013
Entry information
Open.
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
1
References
Legislation relevant to this unit standard includes but is not limited to the Health Act
1956, and Resource Management Act 1991;
Ministry of Health Public Health Risk Management Plan Guides for Drinking-Water
Supplies (PHRMPGs):
P7.1, Chlorine disinfection;
P7.2, Chlorine dioxide disinfection;
Drinking-Water Standards for New Zealand, Ministry of Health, Wellington, 2000 and
2005.
 New Zealand Qualifications Authority 2016
24970 version 1
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2
Definitions
Critical points – points in a process or in equipment where failure to function correctly
can lead to a public health hazard.
Optimise – adjusting plant input variables to make the process as effective as
possible in order to achieve the desired output.
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
Optimise and manage chlorine disinfection processes, variables which determine their
effectiveness, and design features.
Performance criteria
1.1
The mechanisms by which chlorine compounds inactivate micro-organisms are
optimised and managed in relation to chlorine disinfection processes.
1.2
The variables which determine the effectiveness of disinfection are optimised
and managed in relation to chlorine disinfection processes.
Range
1.3
includes but is not limited to – contact time, temperature, pH,
turbidity, organic loading, chloramines, chlorine demand.
Design features are optimised and managed in relation to chlorine disinfection
processes.
Range
sizes, configurations.
Element 2
Optimise and manage the equipment used, methods of application, and safety
considerations for chlorine disinfection processes.
Performance criteria
2.1
Storage and delivery mechanisms of chlorine which can contribute to under or
over dosing are optimised and managed in relation to chlorine and chlorine
dioxide disinfection processes.
2.2
Monitoring equipment used for disinfection is optimised and managed in relation
to chlorine disinfection processes.
2.3
Safety considerations when handling chlorine are optimised and managed in
relation to chlorine disinfection processes.
 New Zealand Qualifications Authority 2016
24970 version 1
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Element 3
Optimise and manage operating issues associated with chlorine disinfection.
Performance criteria
3.1
Operating issues are optimised and managed in relation to chlorine and chlorine
dioxide disinfection.
Range
flow rates, continuity of power and chemical supply, dose rate
adjustment and control, alarm response, disinfection of by-product
formation, drinking-water standard transgression, corrosion,
disinfection by-product formation, equipment failure, safety of
public, equipment calibration and servicing, record keeping.
Element 4
Identify critical points, hazards, and preventive and corrective actions, in chlorine
disinfection processes.
Performance criteria
4.1
The critical points in chlorine disinfection processes are identified in accordance
with organisational procedures.
4.2
The hazards at each critical point are identified in terms of the causes of the
events leading to their occurrence, and the risk factors.
4.3
The preventive and corrective actions for events related to each hazard are
identified.
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.
 New Zealand Qualifications Authority 2016
24970 version 1
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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