NZQA registered unit standard
27895 version 1
Page 1 of 3
Title
Evaluate pretannage processes for woolskins
Level
5
Credits
Purpose
5
This unit standard is for experienced people wishing to develop
their technical skills in leather manufacture.
People credited with this unit standard are able to: demonstrate
knowledge of pretannage stages used in woolskin
manufacture; evaluate chemical mechanism of woolskin
pretannage stages; evaluate woolskin pretannage effects on
end product characteristics; and evaluate potential damage to
woolskin product from incorrect pretannage processing.
Classification
Fellmongery and Leather Processing > Leather Processing
Knowledge
Available grade
Achieved
Explanatory notes
None.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of pretannage stages used in woolskin manufacture.
Evidence requirements
1.1
Woolskin pretannage chemical stages are outlined in correct sequence in terms
of their purpose.
Range
1.2
evidence is required of two, which may include but are not limited
to any of – soaking, scouring, pickling, preliminary tannage.
Woolskin pretannage machinery is outlined in terms of mechanical principle and
function.
Range
evidence is required of three, which may include but are not
limited to any of – flesher, wet shearer, de-burrer, hydroextractor,
process vessel.
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27895 version 1
Page 2 of 3
Outcome 2
Evaluate chemical mechanism of woolskin pretannage stages.
Range
evidence is required of three of the following – soaking, scouring, bleaching,
pickling, preliminary tannage.
Evidence requirements
2.1
Chemical mechanism of woolskin pretannage stages is evaluated in terms of
effects of reagents on skin and/or wool.
2.2
Woolskin pretannage chemistry is evaluated in terms of practical process
control.
Outcome 3
Evaluate woolskin pretannage effects on end product characteristics.
Evidence requirements
3.1
Woolskin pretannage effects are evaluated in terms of their influence on leather
and/or wool properties.
Range
evidence is required of four, which may include but are not limited
to any of – wool length, wool colour, matting, softness, wool
grease, skin grease, suede quality.
Outcome 4
Evaluate potential damage to woolskin product from incorrect pretannage processing.
Evidence requirements
4.1
Potential damage arising from incorrect pretannage processing is evaluated in
terms of faults in woolskin product.
Replacement information
Planned review date
This unit standard replaced unit standard 8402.
31 December 2017
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
21 February 2013
Primary Industry Training Organisation
SSB Code 101558
N/A
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27895 version 1
Page 3 of 3
Consent and Moderation Requirements (CMR) reference
0033
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
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 Primary Industry Training Organisation standards@primaryito.ac.nz if
you wish to suggest changes to the content of this unit standard.
Primary Industry Training Organisation
SSB Code 101558
 New Zealand Qualifications Authority 2016