NZQA registered unit standard
21172 version 3
Page 1 of 4
Title
Demonstrate knowledge of removal, and remove dross and ash from
a galvanizing kettle at a hot dip galvanizing facility
Level
3
Credits
2
Purpose
People credited with this unit standard are able to: demonstrate
knowledge of the removal of dross and ash from a galvanizing
kettle; identify, evaluate, control, and monitor health and safety
hazards of dross and ash removal; and remove dross and ash
from a galvanizing kettle at a hot dip galvanizing facility.
Classification
Industrial Coatings > Hot Dip Galvanizing
Available grade
Achieved
Entry information
Critical health and
safety prerequisites
Prerequisites: Unit 3800, Operate a radio remote or pendant
controlled overhead crane and lift and place regular loads; Unit
25130, Describe hazards, safety and emergency procedures,
and exhibit safe working practices at a hot dip galvanizing
facility; and Unit 25133, Demonstrate knowledge of venting and
draining for hot dip galvanizing; or demonstrate equivalent
knowledge and skills.
Explanatory notes
1
The current version of the following documents must be complied with:
Health and Safety in Employment Act 1992;
Health and Safety in Employment Regulations 1995.
2
It is recommended that assessment against this unit standard follows or is concurrent
with assessment against Unit 21174, Demonstrate knowledge of hot dip galvanizing
discharges and waste.
3
Definitions
Ash is a mixture of zinc oxide and varying quantities of entrained zinc that forms on
the surface of a galvanizing kettle.
Company procedures refer to all documented policies and procedures of the
candidate’s employer at the time of training including, but not limited to, those relating
to health, safety, environment, quality, and operations.
Dross is the alloy of zinc and iron that settles on the bottom of the galvanizing kettle.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
21172 version 3
Page 2 of 4
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of the removal of dross and ash from a galvanizing kettle.
Evidence requirements
1.1
The purpose of dross removal and the dross removal method are described in
terms of company procedures.
Range
1.2
purpose includes – heat, bath capacity, quality.
The purpose of ash removal and the ash removal method are described in
terms of company procedures.
Range
purpose includes – heat, quality.
Outcome 2
Identify, evaluate, control, and monitor health and safety hazards of dross and ash
removal.
Evidence requirements
2.1
Health and safety hazards are identified and evaluated in terms of legislative
requirements and company procedures.
Range
includes but is not limited to – lead, noise, burns, heat, splashes,
dehydration, emissions, hazardous materials, obstructions, people
in the vicinity, personal injury, spills, heavy lifting, transferring
between kettle and container, repetitive tasks.
2.2
The procedures for monitoring and controlling health and safety hazards are
described in terms of legislative requirements.
2.3
Health and safety hazards are controlled and monitored in accordance with
legislative requirements and company procedures.
Range
2.4
hazards include but are not limited to – lead, noise, burns, heat,
splashes, dehydration, emissions, hazardous materials,
obstructions, people in the vicinity, personal injury, spills, heavy
lifting, transferring between kettle and container.
Methods of avoiding dehydration are described in terms of work factors to be
considered and ways of controlling their effect.
Range
factors – humid atmosphere, clothing, equipment, physical
exertion;
controls – type of fluid, timing of fluid intake (before physical
activity, during physical activity, after physical activity), personal
protective equipment.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
2.5
The observable symptoms of dehydration are identified and described.
Range
2.6
21172 version 3
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evidence is required for at least three symptoms.
Rehydration is described in terms of frequency of intake and effect of
substances on fluid replacement.
substances – water, fruit juice, soft drinks, sport drinks, salt,
alcohol, caffeine.
Range
Outcome 3
Remove dross and ash from a galvanizing kettle at a hot dip galvanizing facility.
Evidence requirements
3.1
Dross is removed from kettle in accordance with company procedures and with
minimal zinc drag out.
Range
all dross is removed, dross is cut and/or vibrated.
3.2
Dross is transferred to mould without spillage in accordance with company
procedures.
3.3
Components in dross are separated and disposed of in accordance with
company procedures.
3.4
Ash is removed during and after the galvanizing process in accordance with
company procedures.
3.5
Ash is transferred to container with minimal zinc drag out and in accordance
with company procedures.
Planned review date
31 December 2019
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
21 October 2004
31 December 2016
Review
2
23 January 2009
31 December 2016
Review
3
16 April 2015
N/A
Consent and Moderation Requirements (CMR) reference
0114
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
21172 version 3
Page 4 of 4
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA,
before they can report credits from assessment against unit standards or deliver courses
of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and
which are assessing against unit standards must engage with the moderation system that
applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies
to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR 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 NZ Motor Industry Training Organisation (Incorporated) (MITO)
info@mito.org.nz if you wish to suggest changes to the content of this unit standard.
NZ Motor Industry Training Organisation
(Incorporated) (MITO)
SSB Code 101542
 New Zealand Qualifications Authority 2016