19348 version 2
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Optimise and manage separation processes for drinking-water
treatment
Level
5
Credits
4
Purpose
People credited with this unit standard are able to: optimise and manage
separation processes used in drinking-water treatment; and identify critical
points and hazards, and identify and manage preventive and corrective
actions, in separation processes and systems.
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.
Drinking-Water Standards for New Zealand, Ministry of Health, Wellington, 2000 and
2005.
2
Definitions
Critical points – points in a process or in equipment where failure to function correctly
can lead to a public health hazard.
 New Zealand Qualifications Authority 2016
19348 version 2
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Optimise – adjusting plant input variables to make the process as effective as
possible in order to achieve the desired output, taking into account the constraints of
cost, human input, water quality, and water demand.
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 separation processes used in drinking-water treatment.
Performance criteria
1.1
Separation processes used in water treatment are optimised and managed in
terms of their flow paths, operation and performance factors.
Range
1.2
gravity settlers must include – flow distribution, retention time,
suspended solids loading, temperature, light, wind, short-circuiting,
floc size, sun-floc;
buoyant media clarifiers must include – inflow, outflow, turbidity,
solids removal, settlement, headloss, media flotation;
air-based flotation systems must include – air bubble attachment,
particle rise rates, flow distribution, loading rates, float removal;
evidence is required for at least one process.
Sludge collection is optimised and managed in terms of minimising water
losses.
Range
gravity separation may include but is not limited to – sludge cone
weight, time, variable time, effluent turbidity;
evidence is required for at least three.
buoyant media may include but is not limited to – air scour
process, upflow rate, water backwash, media capture;
evidence is required for at least three.
air-based flotation may include but is not limited to – water and air
recycle rate, loading rate, float-off mechanism;
evidence is required for at least three.
 New Zealand Qualifications Authority 2016
19348 version 2
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Element 2
Identify critical points and hazards, and identify and manage preventive and corrective
actions, in separation processes and systems.
Range
may include but is not limited to – buoyant media clarifiers, gravity separation
systems, air-based flotation.
Performance criteria
2.1
The critical points in processes and systems are identified in accordance with
organisational procedures.
2.2
The hazards at each critical point are identified in terms of the causes of the
events leading to their appearance, and the risk factors.
2.3
The preventive and corrective actions for events related to each hazard are
identified and managed.
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